The "I will take down tracks whenever I want" and "if you buy the whole album, you'll get any extra tracks I upload in the future" messages seemed skeezy at the time. Still does.
That said, many of these albums are good value, even if no extra tracks are added (beyond the extra tracks added already). But alternate mixes / speed versions / demos don't really do it for me.
But hey, Aphex usually proves me wrong--a day after I post this, he'll post so many new tracks I'll look like a total dick. I'd be fine with that.