I've tried mintex pads of differing flavours on a number of my cars in the past, including the GTiR and have never got along with them. Whether it's my style of braking or what, i'm not too sure. But any other material I use, I get on with and don't have a great deal of trouble with.
I currently have EBC Yellows front and rear, and bang for buck they are pretty good. Pedal feel isn't outstanding, but they inspire a lot more confidence than 1144's and 1155's imho.
Ben, If you're new to the 'ring you'll be using the brakes a heap more than you would once you know where you are going, there aren't any real big stops on the circuit at all.