I'm close to an elderly (mid-80s) couple who got it 5 and 3 weeks ago, and reported only very mild cold-like symptoms for a day or two after the second dose.

My greater concern is the potential for mRNA-related autoimmune reactions once the genetic component is broadly expressed. That would not become a problem for many months, but if it does, when it does, it will be irreversible, torturous, and almost certainly lethal for those so afflicted.