Well, the E7200 has 2.53Ghz, and the E4500 has 2.2Ghz. The L2 cache is 3mb as supposed to 2mb. Also, the FSB is greater: 1066MHz, as supposed to 800MHz, and the E7200 is 45nm, and the E4500 is 65nm.
So, yes there is a good difference if you have the money to get it, then it would be a good investment.
Cheers!