Well, it's been a long time and I finally decided I prefer the JAMC version. The Pixies one is alright, but the JAMC one is longer (awesome breakdowns with na-na-na-na-na guitar bit) and Jim's vocals are wicked cool. It's still a fucking awesome song regardless of who does it.
I absolutely love both Pixies and Mary Chain, but this really is NOT a good cover at all.. a cover should sound different from the original, and this sounds exactly the same only a lot worse. It's also as unnecessary a cover as it is unsuccessful, I'm afraid to say. Pixies rule, just not on this song