Help with UCSD college system?

I just got my acceptance to UCSD (yay!) and I am in Eleanor Roosevelt College, which was my third choice. My main concern is that I applied for mechanical engineering, and on my acceptance letter it says I’ve been admitted as an undecided. Also, most people seem to agree that ERC is geared more towards liberal arts, English, or history majors, so does anyone know if I’ll have issues as an engineering major? Any pros/cons about ERC are really helpful as well.
I also applied to UCLA, UCI, and Berkeley, but haven’t gotten anything back from them yet. If I pull off a miracle and get into all of them, which is the best for engineering?
Thanks everyone!

I’m a UCSD graduates. The college system doesn’t matter unless you HATE WRITING that much. From what I heard from friends ERC’s modern world study is the most interesting writing class. Unless you are in Muir (only 8 units of writing), every other college doesn’t matter too much. Usually, once people finished their 1st or 2nd year which college doesn’t even matter.