Great research -- it was sure to get published, probably will be followed by several follow on pubs, and a real lack of value for the general population. /sarcasm
My personal experience:
1) Lower success rate (overall)
If you have a small number of seats in an entering class, as a faculty you are likely to be highly selective for all.
If you have many seats available, it is almost a sure thing that the selection process will be balkanized, with more seats filled by individual faculty members and relatively fewer by a rigorous selection process. In my experience, at least.
2) Studs and studettes (high achievers)
The larger the lab, the more money, prestige, and pubs. Very difficult for smaller progams to compete. Overall, the "very best" students will disproportionally go to the most recognized programs.