I bought it about 2 months ago. Including a 1GB microSD (from eBay) it cost me about $50, which is the best deal I could find and a killer deal for something that does so much. 1GB microSD costs about $10 and 2GB about $30, so if you want to save some cash but still want the 2GB of storage, try for 1GBx2. I bought the Chinese version from Sky2K.com since it was cheaper (and because they didn't say it was Chinese).
I can't really compare it with the other slot 1 stuff, but it works great and you get more than you pay for. It includes a microSD USB adapter and a plastic/rubber case for the R4DS.
I use it mostly for podcasts and the occasional movie, and of course homebrew. About 8 hours of high quality DPG video can fit on 1GB, and I have about 100 homebrew games and apps taking something like 150MB.
I reviewed some of my favorite homebrew in my podcast,
Gamers' Consideration Initiative episode 1, that you might want to check out.
I think you already figured out that I highly recommend R4DS.