I've heard alot of good deals coming from Fasttech but maybe it's just my paranoia that keeps me away from them. That's just me. I try to be cautious.
After my initial order where the computer system screwed up my info and it took me a week to notice it and straighten out[My Fault] they were quick once I brought to their attention.
I've been buying all my Batteries and some odds and ends from Fasttech and they've been excellent.
My K100 from Fasttech was authentic Kamry and excellent also.
My phone charger which takes two 18650 batteries was decent quality.
The Sony 30 Amp Batteries and the Hybrid Panasonics are tremendous deals each for different purposes.
The 30 Amp Sony kicks out higher voltage under load but doesn't last long. The Panasonic Hybrids perform just a tad less then the Sony but last longer. I've gotten 6 hours on my Bogger Box Bottom Feeder Standard Unit with the Panasonic 2900mah High Drain Battery.
Pretty awesome.!!