http://data.typeracer.com/pit/profile?user=vonunov Those last ten races were on Topres. I'll pick an English competition on 10fastfingers.com and do it with Topres, blacks, and blues to compare on equal ground. I'm not used to the blues so who knows what'll happen though.
Topres: 157 WPM, no errors.
Blacks: 153 WPM, one word wrong (5 erroneous keystrokes out of 771).
Blues: 156 WPM, one word wrong (6 erroneous keystrokes out of 786).
So it looks like pretty consistent results, with some stumbling on the blacks and blues as I'm more used to the Topres. Those are all first-try results for each keyboard; I resisted the temptation to redo the tests until they looked good.
My favorite of all time is still buckling springs. I got that 200 WPM on Typeracer on a 1391401. It was like two lines of text, granted, but it's still my fastest recorded speed.
I just remembered I put the black/firm o-rings on the MX Blacks board. Not sure how it would differ but I'm not keen on taking them off just at the moment. It's still a pretty hard landing and I have to "bottom out" to be sure, so it's tiring. Double-taps are especially easy to screw up.