First, I can confirm that 8sp Ergopower shifters work very well with an 8sp compatible Campagnolo RD and a 7sp HG freewheel. I've been using this setup.
I have another bike with a complete Shimano 64xx group, but I don't want to use the STI and will go with a 9sp cassette (I have purchased one with the cogs I want). I could use indexing bar ends, DT shifters, Retroshifts or Shimano 9sp STI units. But, I don't want to. I would like to use Ergopower shifters. So, here is what I would like to use:
Shifters:
2011 Campagnolo Veloce Power Shift (EP 11 VLXSC)
RD:
RD-6401 with
JTEK ShiftMate #2
FD:
FD-6401
Cassette: Shimano 9sp on
FH-6402
Does anyone forsee shifting issues with either the front or rear derailleur with this particular setup?