rotaries can definitely be very reliable. mine had 160k miles on it when i sold it and it was running beautifully. i had taken it to chicago and steamboat springs with no probs a couple of times when it was in the 140s. there are some parts to watch out for though. if the metering oil pump or a few other very tiny parts go out you may be looking at a couple grand just for the part. luckily though you can usually just swap the engine then for less. or just drop in a v8 with a little help from granny's speed shop.
