Here are my thoughts on the inner rain liner: I have the Savannah II suit. The liner is on the inside. If I get caught in a rain I'm not about to stop, take off my outer wear and then put on the liner and outer wear. I'll either just get wet, or put the liner on over the outside. But even if the coat gets wet, it really doesn't get waterlogged, in the sense of absorbing a lot of water. It's a non-abosorbent type of material that will dry fairly quickly once the rain stops.
I use the liners in cooler weather because without them the suit is pretty porous.