it was discontinued years ago. CycloDS Evolution is the best, but its DS only. If you want DSi support, acekard2i is the best, but if you want to be able to play GBA roms on DSi then the supercard DSTwo is your only option
My opinion? Hardware wise SC DSTwo is the best if you plan to use both nds and gba roms. If your only planning on playing nds roms then the Cyclods is the best. But software wise Acekard 2 is the best. But over all i'd recommend the SC DSTwo since it has more features avaliable to it (It has a processor built in allowing it to do things other cards can't. The DSTwo supports full gba emulation as well)
the hardware is not made anymore, nor is it supported by the original team. Thus, it is by definition discontinued.
thanks guys, I'm pretty late to the R4...best accessory for the DS EVER love my R4 and want another one but don't want to end up with a clone so I think I'll go with an acekard...only because if I run into any issues there will be great forums like romulation with knowledgeable people to help simple and easy to use....R.I.P R4