Hi, this is the flatmate.
I have to agree with dobbs, it can get pretty busy between 8 and 10 pm, especially on Mondays and Tuesdays, but the rest of the days are okay. Went today (Wednesday) and there were a maximum of five people in the weights room at any one time. You would have enough space to do dead lifts and no one ever seems to use the squat rack.
Towards the Christmas holidays it begins to die down, by next term it's going to be packed because everyone's going to have a new body-building resolution and they're going to want to see the 'new' gym.
I used to go at 7 in the morning, as you can imagine that didn't last long. The gym was completely empty, apart from one guy who worked out religiously, but I just felt completely dead and drained at that time. You might want to try to see if it works for you? It stays quiet until about 11 so, depending on how long your workout is, you might not need to wake up ridiculously early. I would go at that time but I like to work in the morning.
I was told that between 2 and 4 in the afternoon is good, I've only been there at most three times then but it has been quite empty.
Hope that's helped, good luck with your workout.