Well, most hardcore fans of the series will tell you that Pure is easier (because it's more like the older games), but personally I find Pulse much easier, especially considering it's useless AI
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Pulse also has very "direct" handling compared to other Wipeouts, which can be easier for some people (especially those not used to the "floaty" Wipeout style).
I'm surprised that you feel Pure is faster though - you're only the 2nd person I know of to have said that. I find Pure frustratingly slow, even on Phantom, while Pulse feels like the fastest Wipeout to me.