You can scratch out the Acekard 2i - it doesn't work on the latest firmware of the 3DS (Yet?) and there's no update in sight.

Additionally, R4iGold from www.R4iDS.cn is said to be the second-best cart on the market, the first being the DSTwo, of course. No other R4 is guaranteed to work on 3DS's and DSi's these days, so it's your risk. All R4 carts these days are clones - the real deal is no longer manufactured. The R4iGold from R4iDS.cn is the closest to the original though and it's continuously supported by Yellow Wood Goblin, the creator and maintainer of Wood Firmware, your best choice when it comes to R4 menu's/kernels.

This post has been edited by Foxi4, Mon, January 7th, 2013 at 18:01