To the guy that says heat will loosen the screw clamp connections, I would ask hiim to have a look at his main panel before making such comments. All those wires must be wiggling around!
When we see PUSH IN connections on breakers and neutral bars, I'll be the first to use them.
comparing a STAB, clamp, double sided connection to a bus bar or a meter terminal to chinese push in outlets is absurd.
The ONLY advantage one might mention is if the electrician is mildly forgetful and neglects to turn the clamp screw at all. If you are a dopey electrician, by all means STAB dont SCREW!
Last edited by Thatguy; 11-14-2010 at 02:07 PM.
It seems that main panels and breakers use screws with threads a bit "tight" or a slight interference fit. Back stab screw terminals have a bit of angular offset which gives flex, as well as [typically] serrations on the tab.
Always the issue is that copper and aluminum are soft and re-torquing should be done.
Just an extra 2 cents as I have had problems with push-in units. Perhaps there is a bit more sensitivity to manufacturing tolerances/errors/materials variance in the push-ins.