I meant to include this link before. Since I didn't I will include it now with a fuller quote and BOLD a few words to get my point across more clearly:
http://www.nebraskamed.com/COVID/how-the-johnson-johnson-covid-19-vaccine-works

"How new is adenovirus technology?

Researchers have been working with ADENOVIRUS VACCINES SINCE THE 1970s. Another use of the same adenovirus-based vaccine platform from Johnson & Johnson is in development against Ebola, and another against HIV. "Thousands of people around the world received this type of vaccine in clinical trials for Ebola and HIV," says Dr. Brett-Major. "ONE OF THE REASONS IT WAS APPROVED QUICKLY IS THAT THE SAFETY DATA WAS ALREADY THERE."

AstraZeneca has also developed an adenovirus vaccine for COVID-19. It uses a different adenovirus from the one employed by Johnson & Johnson.
Also, unlike the Johnson & Johnson product which cannot replicate, the AstraZeneca replicates in the body a limited amount.

mRNA vaccines: Moderna, Pfizer
Adenovirus vaccines: Johnson & Johnson, AstraZeneca, Sputnik V

How J&J is different from mRNA

The Johnson & Johnson vaccine is not an mRNA vaccine (like Pfizer and Moderna). All three vaccines deliver genetic material to your cells: mRNA vaccines deliver mRNA, and (1) JOHNSON AND JOHNSON DELIVERS DNA. (2) ANOTHER DIFFERENCE IS THE DELIVERY METHOD USED used – either a little enclosure made of fat surrounds the genetic material, or in the case of Johnson & Johnson, an adenovirus carries it. But the end result is the same: both the mRNA vaccines and the Johnson & Johnson vaccine help your body to develop antibodies against the coronavirus spike protein.

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Some viruses only have RNA and some use DNA to encode themselves. An adenovirus is a DNA virus - it doesn't contain any mRNA.

There were already a wide range of vaccines.

The original vaccine was to actually CONTRACT the virus and recover. It was figured out pretty quickly that if you got pre-exposed to a small number of viral particles your body had a better chance of killing them all before they could replicate enough to kill you.

Then Pasteur discovered that he could pull the same trick against smallpox by using a SIMILAR looking virus: the cowpox virus.

Then they tried DEAD viruses of exactly the type which actually caused the disease (the danger here is that you can't always be sure all the viruses are dead AND you can't be sure the dead virus will still look enough like the live virus AND provoke a full enough immune response.

Then "attenuated" viruses were used: cripple the virus so it can't replicate in volume and infect the host...with a weak ass variety.

Then the idea was if a disease had ONE specific feature which distinguished the disease virus sufficiently from other viruses, you could use a fairly harmless virus and insert coding for the ONE SPECIFIC FEATURE.

The thing is, for a vaccine to be effective you need to somehow subject the body to (a) a DISTINCT ENOUGH PROTEIN (shape) in (b) SUFFICIENT ENOUGH QUANTITY.

If you can pull those two things off correctly, *SAFELY*, you can protect against developing the full disease under uncontrolled condititions.

The mRNA vaccines are differentiated because they ONLY give you an injection of mRNA. The J&J vaccine doesn't inject you with ANY mRNA - it injects a complete, crippled DNA-containing virus, and lets your body take over from there.

Which would you rather get: the actual disease virus in a hardy form or a completely unable to reproduce virus in a really weak-ass form?

If you want to say you don't want "spike proteins" at all, well that's understandable...but if that isn't a choice...if you are just about SURE to eventually contract the spike, one way or another, do you want to just take your chances with the disease (which contains the spike) or with the spike delivered in very attenuated form via a mechanism which has been tested for safety for 50+ years?

Or do you just want to put your life on the line with a Frankenstein experiment which is EXTREME in both the types and the quantity of "newness"...and the COMPLETE lack of long term, detailed, safety testing?

The point is that J&J does contain encoding for spikes -- but it is NOT proper to call it a "mRNA vaccine" -- which now has a distinct definition.

mRNA is a pure Frankenstein experiment. I'm trying to think of something stupid/reckless enough to compare it to. Okay, here we go:

Let's say it is 1943 and you come up with this "atom bomb thingie". Now you really want to win the war against Japan and Germany (save Democracy and all that) but you don't have a sufficiently localized delivery mechanism.

But you expose a few people to some radiation and notice that a week later they are still alive. So you decide:

Let's drop 1000 of these atomic bombs on every place where the Japanese are ensconced all at once. It will melt their infrastructure down, people will still be alive a week later, and we then move in and capture them all.

THAT is pretty comparable to the stupid-ass idea of these mRNA "vaccines". Not only was the mRNA "vaccine" an experiment, it was an experiment on top of an experiment, with 1000 variables not tested and not anywhere near more than "some. people are alive a few weeks later, so it must be safe" thinking.

AND Covid was NEVER anywhere near deadly enough to justify conducting this level of Frankenstein experiment on the whole of humanity.

The J&J vaccine was relatively much, much, much, much much more likely to be relatively SAFE -- with few variables and controlled exposure.

In retrospect, given that Covid never had a mortality rate over 1%, once use of steroids to stop inflammation was "discovered" as an easy and safe intervention. Therefore, use of the mRNA gene therapy on all of humanity under a EUA was about as necessary as nuking all of humanity in order to win the war against the Japanese empire.

Now, all that said, although the J&J vaccine is relatively conventional and well tested, even it was an experiment. And carpet-bombing all of hummanity with a "vaccine" during the midst of a pandemic was, itself, a massive experiment WHICH EVERYTHING THE BEST EXPERTS KNEW ABOUT SUGGESTED WAS STILL ANOTHER GRAND EXPERIMENT and probably not wise. But if you were going to get one versus the other, J&J was the relatively sane way to go.

It might yet have its own buried issues. But it was relatively well safety tested on basics and the latest data shows an "all cause mortality" profile **BETTER THAN UNVACCINATED**.

So you have to pick your poison. Personally, I like the LOCALIZED prophylactic safety vs efficacy data on Vit D, Zinc, steroids, and even Ivermectin, considerably better vs. experimenting on all of humanity for something not too much worse than a bad flu -- especially for younger humans.

TL; DR: *IF* spike-virus is going to come back again (I don't know why it would since the ideosyncratic spike seems to have already been selected against by nature) I would either choose the J&J....although an attenuated Omicron (or exposure limited to only a few particles at a time) seems a lot smarter, safer, and probably vastly more effective: there is growing data that the more times you are "boosted" the more prone to infection you actually become (again, the vaccine spike isn't found on Omicron...so there is no good reason why it would work at all on Omicron at all...and it doesn't appear to.)

Apologize for the run on. Hopefully there is some value in there somewhere. ;-/

I have come to realize that men are not born to be free. Liberty is a need felt by a small class of people whom nature has endowed with nobler minds than the mass of men. -Napoleon