Yep. You don't actually have a trial, per se. You just have a prepaid time card for the subscription. It's the same thing as purchasing a 4-month period on the marketplace. The Dreamspark one, on the other hand, is a trial to the service which is why it is restricted.
Glad to hear the reviews are working for you. Too bad most games aren't available for review anymore. :). I missed it too what with having to work and all...