I don't know of a single quake player that uses 2in/360. Most quake players use accel though, so it's a bad comparison.
I will say that rapha hits 45+ lg with an 8.2 in and hal9k in cpm used to hit better than that with faster sens's.
as for soldier 6-11 seems to be a good range, there are people on each side of that spectrum that are still really fucking good so it's really down to just whatever you're comfortable with. I would say you should be comfortable moving around because I personally think it's easier to train aim at a faster sens than endurance/speed at a slower sens