if you mean in town and the ridgeway whole area got rinsed from 10 years ago and locked off by TVP because mupppets kept smashing up the warehouses, and one crew totally overdid partying in the ridgeway. Bear in mind the whole area is not that big compared to East Anglia or Yorkshire or other parts of England.
I lived there from 1977 to 1989 and 1992 to 2006 (moving back to London from 1989 to 1992) so basically grew up around the rave scene in both London and Reading. but by 2005/06 unlicensed events and the organisers were really under serious pressure from TVP. All my mates who I once put them on with either left the area and did them elsewhere (including outside the UK) or turned their attentions to legal events.
If you have a vehicle and/or do not want to confine yourself to psytrance events in London (which are about the safest in the capital) you are probably better off travelling further, though if you can afford it (might work out cheaper in the long run) I would suggest doing so in a modest and mundane vehicle rather than anything flash. Not so much because of paranoia from fed (though looking like a obvious gary boy will usually get a stop as the traffic cops are genuinely worried about the risks from DUI as it has hurt far more folk than just doing drugs themselves) but fuel costs and the great risk that you are going to probably wreck anything modified/customised by trying to drive it along a farm track intended for tractors
