What happened to Toras Moshe (ToMo)? I have never heard of Portnoys.
It depends on the type of boy going. I think Senter’s is more the Flatbush/In-Town crowd.
Beis is a mix, combination of Chofetz Chaim type guys (but NOT CC guys) and out-of-towners.
Mercaz (Hatorah) may be the “new top place”, but the truth is that Mercaz has been around for many years. Perhaps now is when it is getting more recognized as an outstanding yeshiva. I think a lot of 5-Towns guys go there.
Hatzlacha!