i would suggest not attending any law school with the intent of transferring. sure it's relatively "easy" to transfer from GW to GULC (apparently they take top third), but let me tell you that finishing at the top of your class at GW seems a lot easier BEFORE you begin law school than it is once you get there.
i actually started in GW PT with the hopes of transferring to full time, and then to GULC, in order to "overcome", if not completely erase, the fact that i started PT. we haven't received grades back yet, but i can assure you that i will probably not finish top third. and i really did nothing but study that first semester. that's just how law school is.
i would say go to GULC PT. i think the "backdoor" PT route is a decent way of getting in to a law school of your choice that most people tend to think is worse than it really is. basically, before i started at GW, i heard a lot more people saying that the PT --> FT route is bad, but it was mostly places like this board that i heard things like this. i have never really heard that from people at the school, including those who have actually done it. the "stigma" might exist, but it's not quite like most people imagine it to be. if you do well enough in law school, employers aren't going to care that you took 1-2 less classes your first year.
so if you're planning to do well (which you must be if you're aiming to transfer), there's no real reason to consider GW FT over GULC PT. your employment prospects will be much better coming out of GULC, and if you've done well then no one will care about the PT factor. in fact, they're really more concerned about having an associate with the GULC diploma than they are about their own, personal presitge issues with the PT thing.
the only real pro i see to starting GW FT is that, if you were able to transfer to GULC, it would look really good; employers apparently like transfer students. but is this really worth the risk of not graduating top third at GW and then being able to transfer? is it preferable to starting at GULC PT, where you're very likely to form a community of colleagues who will transfer to FT and finish with you in 3 years? i don't really see why it would be.
i think the GULC PT is a route that more people should take when in the position, but for some reason don't.