Last week I finally organized two friends into a gaming group and held one session.
The old Gamma World systems are obviously not very good, so in hindsight I think it was a mistake to go with it. When I started assembling the group, I had player #1 on board, and player #3 (who missed the first session, but has some D&D experience), and both of them were okay with Gamma World clunkiness. They have mostly played computer RPGs and just some pen&paper stuff.
Player #2 expressed interest in joining us, and I decided to roll with the earlier decision. She has no experience at all with RPGs, but was interested to try it.
The first session was okay - we got through char-gen and some basic introduction and got started on a short story.
I asked for some feedback.
Player #1 liked everything, except the lack of levelling up
my mistake - from all the various Gamma World editions I picked the one (2nd ed.) that doesn't have XP and levels...
Player #2's reactions were more interesting for me, as she has no previous experience with RPGs. Even more, no preconceptions at all. She had fun, but said that she thought it was all "too detailed". She admitted to having a short attention span (although she had no problems sitting through a four-hour long session with a 40 minute break). By "too detailed" she meant everything: we played out some dialogues, there was one fight (taking up maybe 20 minutes IRL?), some investigation and exploration. But she said that she'd like to continue.
A second session will be held next week, with player #3 added to the roster. We'll see how it goes.