We decided to use an equalizer hitch which meant we didn't have a need for a receiver extension. You're right, though, the swinging rear door on the Jeep Liberty with spare on it, doesn't open fully with the Escape attached. We'll probably do a lot of loading/unloading through the rear doors. We have only one propane tank with the two six volt batteries on the front hitch of the trailer and no storage bin. Reese and Dave did not think this was too much for us, but we haven't weighed it to get the exact hitch weight. Because of this, I don't have a recommendation for you.
Jim and Robin