You're not going to find much better than Sky3DS+ when it comes to 3DS flashcarts. Couple it with with CFW so you can run digital stuff, and that's all you could ever need.
Other flashcarts are either Sky3DS clones, or horribly outdated glorified CFWs that don't even run newer games and firmwares.
Sky3DS+ is still worth it for convenience reasons, especially if you already have it anyway, but you definitely should also have CFW.