@kidzer: Funkstar already gave you most of the information. There is also an outdoor running track behind the building. Is RGU Sport the one in Garthdee? I remember that it is pretty good too. If you live near there/study in that campus, then it may make more sense to go there.
One thing they have over the Sport Village (AFAIK - note that I only spent 1.5h at the Sport Village, and most of the time at the gym) is the wall climbing. I am not sure about the price of the one in RGU now (it used to be cheap when it opened) but gym at the Sport Village is about £15 for the gym or £2.10 a pop for students. There are extra charge for other facilities, I think the all access membership is just under £25.
@Funkstar: I just had a look at the TransitionExtreme site. Looks very sporty to me