PreCollege Programs. Are they worth it?

So I’m getting all this mail from colleges telling me about how great they are. Also, I get mail from colleges asking me to go into their precollege programs. These pretty much consist of me taking a few college courses at these universities and living there so I can earn some credits and see how college life is.

What I want to know is if going to one of these programs is worth it. Also, is this a way for a college to gauge how good a student might perform at their institution without having to guess from GPA, class rank and essays. Would I be more likely to make it into that college if I went to one of these and did well?

The one thing that you don’t count on is becoming fiercely loyal to that school. You might have picked it for being close by, but then it seems better than the school that actually specializes in your favorite field.