Just like the title says, what are they for each weapon?
ARs: I love the impossibly rare 3.6 scope, but since its so hard to get, I enjoy using the one with the little dot in the middle (1.4?).
MGs: 2.1 scope for these.
Repeaters: Tricky one.. I pretty much like them all except 1.8 and no scope. The 2.6 is a nice little scope that looks natural on a repeater while the 4.1 works well, but looks fat. 4.7 is a little too much zoom on a repeater if you ask me. Also I love the 3.1 epic ironsights.
Machine pistols: Pretty much the same as above, but I prefer the 3.1 on these more.
Revolvers: Alot of the time I like the no scopes.. I remember having an Unforgiven masher with no scope and it was SO good for Crawmerax. Other than that, I can settle for 3.7 since I use revolvers from the hip.
Rocket launchers: 4.3 or 4.9, launchers need good scopes. The ironsight on these is retarded.
Shotguns: I really like the 3.6 scope because it's not big and obnoxious like the others, it's small cosmetically and just "slots on" and doesn't get in your face. Shotguns, for me, are always used from the hip, but when I need to tighten the spread or have a 70+ acc shotgun, the zoom is great.
SMGs: I think that 3.9 is just right. 4.3 looks really weighty on the gun and is a little too much zoom for it, IMO. I won't pick up any SMG with a 1.7 monocle on it because it makes me heave. No scopes for Anarchies and Wildcats.
Snipers: 2.4 is the perfect one I think. 2.7 (and 3.2!) is a little overboard. The TV screen isn't too bad, I can live with it. The 1.5 is really bad because the slit is gimmicky, looks fugly on the gun, and is hardly an update to a 1.0 scope.