Just remember that you get what you pay for. Cheap chargers tend to charge more slowly and don't do as good of a job. The first review you see on that one you linked, is probably a common issue because the charger isn't smart enough to trickle power to the device once it reaches full. Instead the phone hits 100% and the charger turns off after that. So when you wake up in the morning, it might not be completely full.
Also, cheap Qi chargers tend to be very particular about the placement of the device, making it more of a hassle to find the "sweet spot".
Personally I'd say drop the extra money and buy a name brand one with plenty of good reviews. I'd imagine the LG made one will even charge the G2 all super fast like it's supposed to do.
Sent from CAMACHO, my Verizon G2 (VS980) running PAC ROM 4.3.
The Aphotic Chaotic
LG G2 VS980 (Verizon) [JB 4.3] PAC-man ROM
Nexus 7 [JB 4.2.2] XenonHD