For stock, charge at 6 amps.
For mod, charge at 5 amps.
Use .05 delta for average room temp. If you are outdoors and its hot (80+f), go with .03 If its very cold, go .07
It is important for the pack to be "WARM" but not "HOT". The cells being warm decreases the IR because the chemical reaction happens quicker inside of the cell, releasing more energy over a shorter period of time (car goes faster)
7 amps will give a slight increase in voltage, and as long as you don't overcharge, it "MAY" not significantly reduce the life of the pack, but I don't like to chance my money like that.
If your going to do high amperage charge, set you delta peak at its minimum. At that rate, they can go from warm to way too hot in a hurry.