I went with separates in my car (5 1/4" woofer and 1" tweeter). The money that you are going to spend on a 5X7 would be better spent (with a little more) to buy a good pair of separates. If you are just upgrading the speakers because of a budget, you won't notice the difference. But if you install a high performance amp later, you would really reap the benefits then.
FYI