I originally planned to get a SCDS when they came back in stock at RHS, but I got impatient waiting for them and I bought an R4 (from RHS) which I should receive sometime between the 21 and 23.
One issue that worries me about the SCDS is how it REQUIRES a high-speed flashcart for many games. My choice in flashcarts (Transcend) aren´t liked at all by the SCDS. You get some message about it being too slow and not usable on the SCDS, so I changed my mind and went with the R4 because it´s OK with slower flashcards.
I´m not overly worried about PoR/DoS issues though....I own the actual carts of those, so I´m good.