piggybacks work excellent.
Apex safc is about the most popular this side of the globe. Folks use it with a hacked or bigger mafs + injectors and its not uncommon to make 400 hp to the wheels from mitsubishi 2.0L motors. sr20 guys make ~330, same method. 4ag ~250 on map ecu.
Greddy Emanage does fuel and timing, but costs more.
I plan to use SMT6 from perfectpower.com on my ca18det and 4agte. I know a couple guys running it. Works well, adjusts fuel AND timing and costs the same as the Apex safc... hard to beat. Need a laptop tho