I have heard that factory drivers charge there 3300 packs at 8-10 amps but there junk after one or two times. I charge mine at 5 amps and get a good 2 year use out of them and i do discharge using a cutoff switch. I dont run my car till it quits running. I will run for 5-6min max then put a fresh cool battery in. Everyone has there own way of doing things so always do what works best for you. Starting out i would not charge over 2-3 amps untill you learn how everything works. Never charge over twice the number of the battery.
1200=2.4amps
1600=3.2amps
2000=4.0amps
3300=6.6amps
This is what my local hobby shop (LHS) tells everyone???
Dont leave your battery unatended while charging.
Right or wrong this is just my opinion Thanks