Someone set out a spreadsheet before of the exact same SPR vs STR argument. It was calculated (even with skills) that STR won out unless you got lucky and hit a critting spree. This was of course before CS items that gave you bonus crit. % so it's radically different now.
With there being a real possibility of someone obtaining a 54% crit rate and possibly critting every other hit, STR doesn't look like it stands much of a chance
Is it any different if you count only builds and stock weps, rather than boosting crit % to the max?