What do you think of using a load center in lieu of a regular panelboard? This may be a matter of opinion? By loadcenter I mean a Square D QO or similar. By panelboard I mean a Square D NQOD or similar. A specific situation - a 200 amp 42 space house panel in a small apartment building?
Are you just talking about the difference between using an integral main breaker or a back fed main in the rails? The biggest difference is how many slots you have available after you put in the breaker. It will usually take up 8 of you slots. The other option you have with the Square D NQOD is bolt in breakers. It seems to be available either way.
As far as UL and the NEC care, this is no difference between a panelboard and a load center.
For your installation, the only major differences include: Load centers are designed to fit inside of stud cavities so they are about 3-1/2" d and 14"w. Panelboards cabineets are usually 5-3/4"d and 20"w.
Loadcenters breakers are normally plug-in style while panelboards are more often, but not always (i.e. NQB), bolt-in style.
Steve, I prefer the panelboard in this situation. Unless you have space considerations. If you have a contract w/sq D and they are on it, they can be quite cost effective. I usally use the qo snap in cb but you could use the bolt on its a nice option. More room is better in my opinion.
I'm just looking for reasons to not use a load center. Usually I would use a panelboard unless there were just a few circuits or I had to fit it in a 2X4 stud wall. In this case though it is for the house loads in a very small (10 unit) senior apartment building and is single phase. On the other hand it is pretty full (about 37 circuits).