You have the following options;
1. Gateway 3DS with a retail copy of OOT and a save dongle. (will work with Cubic Ninja SOON... but who knows how long that SOON may be because Gateway lags on everything.. don't expect any update within the next couple weeks unless we're lucky and they change their habit)
or
2. Sky 3DS
and then there's the clones.. I don't know much about the clones but the clones are either based off of Gateway or Sky3DS so I would just stick between those two if I were you.
KARL3DS will be releasing very very shortly as well as OSKA and if you don't know what those are you can look up their main threads on here at GBATemp. I think they'll be using Cubic Ninja as the exploit. However, if you are looking for something to use NOW.. you only have those two options I gave above.
My personal preference is Gateway. I'm using it on a NEW 3DS XL 9.0.0 as well and I love it.
Works flawlessly.. only thing that sucks is that you have to get a retail copy of OOT to run it and you won't find one under 50$ unless you're extremely lucky. I found my copy at a shop that sells used electronics for 50$ and I bought it asap. On ebay its going for 70+ atm.. probably will go up honestly. Unless you don't mind waiting for Cubic Ninja then go with Gateway.
Main difference? Gateway has a TON of features such as support for eShop .cia's, emuNAND, region-free roms, etc. etc. a hand full over Sky3DS.
Sky3DS is more of a simpler plug-and-play ordeal and does not have support for any eShop dumps or emuNAND or anything extra. Strictly drag and drop ROMs and play.
So it all depends on your preference. Good luck!