I'm a slave to speed-mods. Try Sakura using C400 -- it makes it a piece of cake because the tempo-changes are never reflected in the rate the arrows ascend, only in their spacing. I play almost everything with a speed mod of some sort. My system is roughly as follows...
0 to 100 bpm: 3x
100 to 175 bpm: 2x
175 to 225 bpm: 1.5x
Over 225: 1x (or C400 for most 10-footers)
My friend Evan puts us both to shame by a mile though. He did this ridiculous run on Step-Mania about a month ago, where he tackled just about every 10-footer I had right in a row. His scores were (all within about a 30 minute time window):
dokudenpa - AA - 850 combo
max unlimited -- A
max 300 - B
legend o/ max - A
sakura - AA
paranoia survivor - A
bag -- AA (9 greats)
paranoia survivor max - C