First I hope we are talking paint store Pittsburgh and not Menard's box store version. There is no comparison. The latter is terrible and you do not want it. Runny and it sags just to start. Why Pittsburgh doesn't disguise it like others do their box store brand amazes me.
I have used both paints on interiors with no problems. I have used more Sherwin Williams and certainly more Benjamin Moore but if the Pittsburgh dealer is cutting you the best deal I would have no reservations using the paint. Some people on this site seem to like the Pittsburgh trim paint a lot in fact.
You might see what range of sheens each offers that you like if you are concerned about eggshell. I think the painting contractors are just trying to give you a surface that might be easier to wash and touch up since you have kids. Good thinking on their part.
Better? I don't know. I do know Pittsburg( from the real store) is a little less expensive than SW and is what I use day to day since BM is 30 miles away. I use SW also and have no problems with it. Both paints on the upper end of their product line.