I have the 2s and got them instead of the 3s based on Rod Snaith's recommendation. I like the 2s a lot-- plenty of power. I can also control smoke easily even here at 6000 ft elevation.
EZ and 2s is a great combo. My next step is a PMAX comp. Of course, trans, exhaust, etc. etc. have to come first. I already have as much power as the rest of my truck can handle. I can't go farther without a lot of upgrades.
Injectors are the way to go. The DD directions make the installation a snap.
HOHN