Milhouse, both my cards are the ones from 7 Day Shop and they're just fine. I don't have any qualms buying from them.

Chadsawyer, as for compiling your own kernel it's easy if you follow this guide. You need to apply the SDHC patch which requires a bit of editing as the patch is not taken from the 2.6.18 source but if you're familiar with patch then it's not hard to apply the bits patch can't manage. The bog standard kernel does come with ext3 modules though so as far as kernel supports concerned I don't think there's a problem. Whether the ext3 file system tools are available is another matter.