Hi! I have decided i definately want to do a PhD after i graduate, but cant decide whether to do it at uni or in a research instutute (eg. MRC lab)? any advice on the pros and cons?

The only thing I can think of is that when you are at a uni you will be able to demonstrate/tutor undergraduates. which is good money and gives you experience and lookes good on cv. In an institute you will probably not have the oppertunity.