I lived in Manchester as an exchange student. I lived on Oxford Rd, and for me the location was perfect--within walking distance to everything I needed. (My classrooms and the bar I worked at were literally across the street! hehe)
It's a very compact city, the city centre isn't too spread out, and can be easily explored.-- You say you've been to other places in the UK--what areas have you visited? I could compare Manc to London/Nottingham/Leicester if you wanted.
The Magic buses there are the cheapest I've seen in the UK. Three years ago, it was only ~60p per ride, but prices have probably changed since.
I only really experienced student life there though, and since there are both Uni of Manchester, and Manchester Metropolitan, there are loads of students during term time--going out to bars and clubs, etc. I didn't like the majority of people there, BUT, they were all students, from different places...And, i did end up falling in love with one of my hallmates on accident!
There's plenty to do, and always something going on. I haven't heard it called "gunchester", but there are always places to avoid in a big city. I generally steered clear of Moss Side, as it had a bad reputation, but when I did walk through that area, there was never anybody around. In the city centre, there are quite a few chavs, asking for your money and that sort of thing...
But it all depends where you're living really. Look into it to find yourself a nice area before being overly "gutsy"
