been to a few of these clubs and agree that tunmills is NOT a clubber freindly place with regards to the venue, its too haphazard but puts on good nights (gallery and my mates run one of the back rooms (prehab)).
went to a gatecrasher a few years back and was dissapointed, there just was no magic there for me.
The end is a sick little club with many good nights to be had

there is the egg club in kings x nice intimate and clubber freindly venue.
I did really like Air though nice clean soundsystem and good vibe in there but a little too exposed for me not enough nooks and crannys to get lost in.
My fav though will probably be heaven in london though, so many good nights there ie, bedrock, peach, wildchild, and with three reasonably sized rooms places to hide freindly staff/punters.
an idea though instead of the best in the uk how about best in each country? each country has a different vibe as it were.
As in one of the best clubs in wales is Escape I have not been there yet but have been told its good