It probably depends on your weight. My son (almost 70 kg) got a Warp 9.0 2010 with the recommended Platinum 520 mast, but he found the rig a little unforgiving and soon realised that he performed better with a NP X6 490 mast in the sail (the board was a Tabou Manta 85). He then got rid of the Platinum 520 mast and bought a Platinum 490 (2011 model) instead and have been very happy with this combination.
Just to make it a bit more complicated: When measured the Platinum 490 2011 model mast turned out to be surprisingly soft and surprisingly "far from flex top" compared to most other Platinum masts. For example, I've just bought a Platinum 490 2012 mast, and that one turned out to be a little stiffer overall and have a more "Neil Pryde like" bend curve.
North Sails seems to favour comparable long and stiff masts in their performance sails these days. Ok, they have relatively long luffs, but in a tests of a 2012 Warp 7.8 and a 2012 Ram 7.8 in the French Planchemag magazine theses sails were the only ones with 490 masts, the other brands used 460 masts. The magazine found the sails had very good performance - but perhaps not the easiest sails to sail. And in a test in the German "surf" magazine the test report simply concluded that the tested 2012 North Sails S Type 8.4 didn't function with the recommended 490 cm mast: "Der - auf der Webseite als erster Wahl empfohlene - 490er-Mast ist zu lang, zu hart, zu dick."