We've visited pretty much every one out there, and from observation they were all about the same...and all bad. Well...not like being raised homeless in East LA...but bad in comparison to places (like Seattle Gymnastics Academy http://www.seagym.com/) where the coaches are professionals; highly trained, intent, alert, and THRILLED to be with the kids.
As a former competitive athlete I don't care if my son ever competes (it's about having FUN a learning how to move your body!), but I've got years of experience in evaluating programs and coaches. Little Gyms/etc. are essentially the Free Clinics of tumbling. Sure there are a couple good coaches/doctors here and there, but they're few and far between and you have to be very lucky or search exhaustively. Usually both.
The YMCA would be the next step up. They can't pay very well but they have their pick of instructors...and so many people owe them so much they get a good draw.
The next step up after that would be good gymnasiums. SGA is our hands down favorite. We didn't do the Mom'n'Dad'n'me class...I've got little Mr. Independant...but we did the older classes for some time. There's another good one in Edmonds...I'm afraid I don't know of any eastside...but that doesn't mean they don't exist. :)
One gym to AVOID is Cascade Elite. They talk a good game, but they stick parents waaaaay up out of the way for viewing (a warning sign), and browbeat the kids. YUCK! My gym in CA turned out at least one olympian every 4 years...but they were NEVER mean to the kids training...OR snotty to the ones who were just there for fun. Cascade Elite does both. :P
<grinning> I'm obviously biased, but you did ask for experience.
Good Luck & Have FUN!!!