Looking at the Penn State roster reinforces my position from last season. It looks like they use a 4 man front but their DT (interior linemen) go around 290 to clog up the running game in the middle. The DEs go around 250 so that they are mobile enough to cut down the run to the outside.
Lehigh, on the other hand uses a 3 man front however our NG (interior lineman) has been around 260, no match for a 300 pound lineman and our 295# lineman played to the outside. It is no surprise to me that we gave up a lot of long runs both inside and outside including the lowly Leopards.
I want one of those 285# in the middle.