I've used re040's on track and theyre fine in the dry, but in the wet they are the devils greatest invention!!
I have never driven with any other tyre that is so bad in the wet. Even in a straight line in 3rd gear I could lose traction very easily if care wasnt taken on the accelerator. Was the worst experience of my life and would rather drive on r888's in heavy rain than these. I also had re050a's and I never took to them. Pirelli pzero rosso's were also pretty bad in all conditions except dry.
The best all rounder tyre ive ever used was michelin ps2's.
There was a reason the re040's got discontinued...