I bought my Edirol yesterday along with a Kingston 4GB SDHC Class 2 card, worked perfectly for both recording and playback on a quick test. Will see how it works when recording for longer periods of time.
edit: with 4 shows behind, including two 90min gigs, a 2 hour gig and a 3½ hour gig the card has worked perfectly so far with no glitches. Naturally this can't really be considered long term success but so far so good.