The Unicorn is pretty massive pub with tons of seating, perfect if you're going out with a bigger group of people. Despite the size it still manages that dark dank pub feel without being grimy.
The clientele varies massively and is pretty hard to peg down (anything from 19 year olds to 60+ and everything in between).
They have live music fairly regularly (typical pub cover bands) and the pub is big enough that you can either sit close to the music and really enjoy it or move further away (because of the size of the place) and actually carry on a conversation.
I don't find there to be anything outstanding about this place but if you're looking for live music and decent beer this place isn't half bad.