A suit can make you stand out from other windy's when canvassing commercial but you don't stand out from other "reps". I favour a sports jacket/blazer and smart trousers with a tie for canvassing.
But if I am working and want to put a card in next door or whatever then I'll just do it wearing my work gear.
In jw land when working commercial territory the blokes tend to go with suits (or overcoats if cold weather) but on private homes sports jackets, woolly pullies and ties are used too. In the posh areas this is fine but IMHO in the rougher areas you can be overdressed in a suit (I have been mistaken for a copper or a social worker before now and so tend to dress down a bit although always with a tie.)
It's getting the balance between looking professional, reflecting your line of work and being unthreatening.
If you look at Fawlty Towers in "The Builders" episode - I think you want to portray "Stubbs" ("4 x 2!? Bleedin' cowboys!") rather than "O'Reilly" ("Oi like a woman with spirit Mrs. Fawlty! Oi do! Oi do!")
