ive been to the guildhall on several occasions having seen GC, Dragonforce, Enter Shikari and others there. its a good venue, you can see the stage from pretty much anywhere, its quite a big venue aswell. sound quality is very good, very easy to hear :)  seating is pretty poor but hey ho, i stand. no glowsticks or crowd surfing is allowed though, which kinda sucks.
overall, quite a good local venue

I went to the Guildhall for the first time last night to see Less Than Jake. It's an impressive venue, inside and out. It remind me of a cross between Bristol's Colston Hall and one of the older impressive railway stations. Despite the hotel style carpet, it doesn't feel like going to a gig in your nan's front room. The acoustics and visibility were both good. The bars (3) were modern and well staffed (I didn't queue for more than 30 seconds) but if you're a beer drinker, best you get used to Carlsberg.

The Soul Cellar is nearby and seems a good pub. It looked like they might have live music or a DJ there. Mysteriously, the doubles were cheaper than single measures.

Yates' which is a bit further away won't serve you without ID. Even if you're clearly a grown up.