Im from north london and tend to play:
The Mall (Reading)
Elite Action Games (Dorking)
Dragons Lair (Brentwood, Essex)
Played Bunker 51 a few times, basically its 40 odd people in a place suitable for 15!! faaar too small to actually enjoy yourself and quite frustrating to play. I prefer Mall any day even with the drive.
But then locations depend on if you have access to a car (opens up a LOT more sites if your prepared to drive 90 mins and wheter you want to play woodland or CQB (not so much choice down this way for local CQB except Bunker or The Mall).
But otherwise welcome to the forums and hopefully see you through my red dot one time