I went out and bought the 2 cymbal kit yesterday. I was hesitant because i wasn't sure how well they would hold up, but since my brother was coming over to play i thought why not make things more interesting? I was pleasantly surprised. The cymbals were accurate all the time except when left too loose in which case they registered more hits than they should have, all it takes is turning the top knob for quick adjustments and problem solved. Other than that, they seem well made. The hit area of the plates is solid rubber and seems pretty durable and the attachments, when installed correctly, will keep the pieces in place (we winged the installation the first time and the rods would swing away and/or slide down).
I say if you enjoy the drumming part of the game it's a solid addition. Takes drumming to another level. I'm considering getting a third cymbal, but i'm afraid of overcrowding so i'll stick with what i have for now. Hope this helps.