You should really get a R4i Gold 3DS from R4ids.cn. The R4isdhc.com's menu is slow as hell and I think that it's the same with the R4i-sdhc.com because both have the same manufacturer.
The R4i Gold 3DS however supports the famoust Wood R4 firmware and has basically the same functions in addition to some special ones.
If you want to get something basic, get an R4i Gold (r4ids.cn) which supports Wood R4. These cards don't get outdated too often. Almost every year the DSTT clones, the R4i SDHC cards (r4isdhc.com & r4i-sdhc.com) get outdated. If you want to get something more advanced, get a Supercard DSTWO. It can emulate GBA, GB/GBC, SNES, NES, MAME, and so much more; it can also run cool things like iMenu or BAGPlug.
Super cards are always they best and they pop up every now and again on eBay, but I would wait for the dstwo+ which will be a ds flash card with a 3ds flash cart that pay mises everything gateway has too.
If you already had a Gateway, you could've easily installed flashcardtimewarp.cia and used the Gateway Blue card for DS games. No need to invest money on a new DS card. I still don't think any other card is better than the Blue Gateway card in functionality. The Blue Gateway card can play any and all DS games.
Edit: Except of course the uberly expensive and out-of-production DSTwo, but still, like I said, the blue card will play any and all DS games.