don't do it if it unless its only 1 set in amongst 6-8 different DJ - hip-hop, funk, techno etc...
I went to a great party in East London a few weeks back in a semi-squatted social centre. Started with a band, mixed up funk and d&B and ended with a banging techno set. mix it up but not 90% one genre and 10% another. equal weighting and a complete mix-up is the way, imo