I got the Prev back Friday with the newer engine. It runs great- better than I remember my Previa running in years. My mechanic even replaced my engine and transmission mounts. Only issue is the overflow valve was releasing a lot of coolant initially. I checked the level later after another drive and it was fine. Yesterday the overflow valve once again started releasing fluid but this time it was water and brown stuff. I'm thinking it's the water that I had added to the cooling system when I was on my way to the mechanic but it makes me wonder why the shop didn't flush my cooling system before giving me back the car. I will do it myself today to make sure it's done right, but I can't help but wonder if there was something else they didn't do. Maybe I'm being too picky, but that seemed like an obvious thing to do with an engine swap. If I ever have this problem with one of the other three Previas (I love saying that), I will do the swap myself.