I think there are two points to consider: experience and money. Apartment living is more like real life, so has some value, but there really is nothing like living in a dorm, and you only have the short opportunity to do so. It can be freaky, and the unknown roommate thing is weird, but generally that works out just fine. While dorm living can be distracting it can also help you focus. I made a friend my first semester with whom I used to study every night. There's no way we would have been that focused without each other's support.
I wouldn't worry too much about the summer. A lot can happen in two semesters of college. You might find an internship, volunteer, or study-abroad opportunity. Or you might make a friend with a house in the Bahamas who wants you to come stay with her for the summer. You never know, and if you do end up needing an apartment, there will usually be students with the opposite problem--they will be looking to get rid of apartments for the summer and looking to sublet them. These can often be pretty good deals.
The other issue is money. People who haven't lived on their own often underestimate the costs. You should really put together a budget. It will include rent, utilities (including internet, cable, and phone), as well as food. Food can be a big expense for someone not used to shopping and cooking on their own. If you end up eating out a lot, it is pretty easy to spend $10/day which ends up as $300/month. All in all, it isn't unreasonable to expect to pay $800-$1000/month on an apartment. I don't know what dorms are up to these days but they used to be much cheaper than that.