i'm a bit torn between devil & deep blue sea. someone else has advised me the heavier bigger 19's will get more grip on the rollers.
last time i had it dyno'd it seemed to get grip OK with 18" bk166's, but now its more powerful i'm not so sure.
i remember watching a dyno of a 300bhp rwd saff with comps, a few of us had to sit in the boot to help get all the power down because it was slipping