very bad experience. i usually practice on a steinway (about 100 years old) at school, it is the best steinway i've ever played on, pretty much everything i dream it happens. well, every steinway is different, but i suppose after a 100 years, everything just becomes right.
then... the story begins, a couple of years back i had a recital and my last piece was the liszt hungarian rapsody no. 2, the piano: BOSTON... geez, the keys don't repeat so fast, (if i don't let go the key ENTIRELY, it refuses to make the sound again), in the fast repeating-note section, i sounded so stupid. even worse, the recital was recorded, and the worst, i was given a copy of my recording... ouch...
anybody had bad experiences with having to play on a bad piano during performance?? although steinway is definitely a favorite, but every steinway is different, especially new ones, the pedals are so stiff. i would have to say my favorite concert piano is yamaha. no weird surprises, fast response, granted, the touch isn't quite so great, the keys from yamaha compared to steinway, it feels rather synthatic. nevertheless, you can never go wrong with it