I think you just need to decide on an adequate 4 pot setup Steve. The pads, fluid and discs are the easy part and most swear by Ferodo, Motul fluid, and a disc of your choice.
The other thing to factor in is the cost of replacement discs. I went for the boxster 4 pots because it meant I could stick to the standard size discs which are cheaper than the 323x28 or the 330x28 discs.
It also depends what type of stopping power you need. If you do regular track days then you might want a bigger setup but if it's just fast road driving then a smaller setup may be fine.
Next time you're at a meet you could ask a few of us for a drive to see what the brakes feel and perform like.