ive had sterling in several sizes not bigger than .693 if antything id say use a .689 barrel but if in doubt use a .693
i normally use a unitec kit (.685 .689 .693 bore sizes) the .689 bore seems to work well with their paint.
i disagree. dunno if i'd pay the full price since i got it with a really good discount from new but i've never experienced any problems with shots being inaccurate.