i like both pickups :)
i do agree with Tim the VH2 has more bass than the riff raff, its quite noticeable in fact. both are quite tight pickups though, for PAFs, due to the A5 magnets.
twinfan states the riff raff is a neutral sounding pickup. in the past i've not quite agreed with that.. but recently i've put my riff raff set in a different guitar, and now i know exactly what he means, since it is completely neutral in the new guitar.
i had the riff raffs first in a guitar with what i now realise has slightly scooped mid, and the riff raffs really brought that character out, in the form of a raw and ultradry bite - which was really fine, but very distinctive. the new guitar is more neutral, and the riff raffs reflect that.
my VH2 is in an alder body super-jazzmaster, where it does have a quite pronounced high and good cut, but i wouldn't describe it as a bite - its just a question of metaphors and characters. the vh2 is a little compressed (as much as a PAF can be, which isn't really!)
neither pickup sounds boxy, both are open.