I've been using the 12v ACdelco 3/8 cordless ratchet for a couple months now with fantastic results. It's wonderful. I even kiss it sometimes. Full on mwah! It's rated at 53ft/lbs. Battery life is excellent and charges quickly. Got it on Amazon.
I was inspired by my lead tech to purchase one after using his matco cordless ratchet. They both seem to perform the same. Both have very responsive variable speed triggers so they can handle plastic without over tightening.
The matco ratchet has 2 advantages. One of which I'm envious. His has an led light, and a battery life indicator.
You'll find, however, that the ACdelco product is more economically priced. By at least $100 if I'm not mistaken. Also carries a 2 yr warranty. Not as much as dewalts 5yr, but last I checked it was only pushing 35ft/lbs. I need more than that here in the rust belt.