Depends really on whether you want triple clamps like the Boxxers or single crowns like the 66s, Z1s, Pikes etc.
I know someone with a pair of 06 66RC2Xs and he thinks they're great and I also know someone with Pikes. What type of riding are you looking at doing because the Pikes are All mountain forks and if I remember correctly the Supreme is a DH frame. What about the Manitou Travis forks they look pretty good.
Its the supreme FR 6inch back end travel, Like i said before, im into DH and Jumping mainly on man made type trails, not dirt jumping, Ive been checking rewiws and there sending me into a bit of a tail spin! I like the boxxers as you can dial them down to 130 fo the up hills or have them at 170 for the DH stuff. is there a significant difference between the 05 and the 06 boxxer rides, except the obvious motion controll and maxle, are they worth the extra £100+?
I'm sorry I don't know anything about Boxxers. If I were in your postition I'd go for a long travel sungle crown fork such as a Travis or 66. The Boxxer Rides got a good review from MBUK in their fork test though.
I personally wouldn't bother with the Pikes or Z1s, there both good forks but wouldn't really work with that frame. I think it'll come down to your riding style, if you like to go fast on DH courses etc then you'll be really glad of the stiffness of a triple crown fork.
However, if you like to jump and do things like Xups then go single crown for the obvious reasons but when your really hammering it into rock gardens, roots and berms then you'll start to realise the limitations to single crowns.
If you get boxxers it might be worthwhile getting the compression damper upgraded by Mojo as the stock damper has a habit of spiking on fast square edged bumps. Another good choice would be 888RC2Xs, i think they're better (although heavier) than boxxers
As for single crown, i don't think you can get better than the 66, especially this years RC2X version