You can use rxTools (What I prefer soley for it's built in region free), or you can go with the bandwagon-like CFW known as ReiNand. Both will do you good either way, so you won't miss out on anything if you decided to use one over the other.
You can actually have both on your SD card and boot into either of them anytime.
Emunand is shared between all CFW, the CFW just allows you to enter it with specific patches. So you can still use Gateway, but then also use rxTools by simply booting into it.
rxTools:
https://github.com/roxas75/rxTools/releases (Requires specific files, PM me if you like)
I believe you can use AuReiNand as opposed to regular ReiNand:
https://github.com/AuroraWright/AuReiNand/releases
What I used to do before I got into A9LH: Gateway + rxTools
Basically whenever I wanted to us my Gateway card, I'd use gateway. But if I wanted to just play Cia's and not deal with Gateway's crappy boot rate, I used rxTools.