I'm mixed on RPGA.
It's been a great way to meet other players, and to get more practice at simply playing and strengthening one's grasp of mechanics.
RPGA play has corrected my understanding of a few rules.
I haven't had a good roleplay experience from RPGA, and it often feels more like playing an MMO. Rush through the encounters and collect the loot and hope you get closer to leveling up, with no long-term character meaning. Sometimes some hack and slash can be fun too, but sometimes I want more.
I feel skill challenges especially wanting in my RPGA experience. They often feel tacked into the adventure in a contrived way. They really just don't end up being interesting or fun in practice, at least in the RPGA format. They really break down into a "ok, here's the part of the game where we figure out who has the highest skill, let them roll, and 4 people assist.
The new MyRealms format could be very promising though. Conceptually, it sounds fantastic, but I haven't got to see it executed.
I'd definitely suggest at least giving it a try, for some of the benefits I listed already (game familiarity and networking to meet players... and it's better than not playing at all, even when it's munchkiny hack and slash)