We know mRNA has a relatively short half-life and is not integrated into host DNA. Other than the lipid nanoparticle (which I honestly thought would have caused more problems), what are we concerned about? How long should we wait in the face of a pandemic that has killed over 500k Americans? If you want long-term safety (studies over 2 years in length) you can have it, but it would be at a serious risk to continue to let this virus spread unfettered.Further research on long term side effects or other risks.
I'm sure the first 10 million folks to build homes with asbestos were pretty pleased, too.
Again, the mRNA vaccines are just part of the mRNA of the virus, as a mimic of what the virus would do in the body. You should then be equally/more concerned about a larger payload of corona virus (containing various mRNAs) and it's long-term safety. I think the risk/benefit is pretty clear here.