In Turf Wars the aerospray is the most used by far. In Ranked it depends highly on the rank, up to B+ (included) you see a lot of Gals and rollers, but up from A- there´s more variety. I think the most used weapon may be one of the Blaster variants, but you also get your share of Rollers, Dynamo Rollers, Chargers (in all their variants, even scoped), Elite 3K, .Gals...Inkbrushes aren´t seen in any rank and aerosprays are less common on higher ranks.