Xperia X10 :: Reccommend A Good Case And Bluetooth Set?

I've been considering the need to get a decent Bluetooth headset for use in the car if I get bored on long journeys. But there's many on the market ranging from cheap as chips to bloody expensive, so what ones do people reccomend for use in the car? Ideally it would need to be easy to operate while driving, have decent reception and clarity and if it comes with a holder you can mount on the dashboard, even better as I could use the phone for Google Navigation and sell my TomTom if need be!

Also cases, similar issue. At the moment I use those clear plastic ones you clip on each side that you get for like 2 quid on Ebay. They work great and have protected the phone from many a fall. Problem is, grime shows up on the plastic very clearly and you get dust/hair/dirt getting clogged underneath the plastic case. So I'm thinking of spending the case to get something half decent that won't impede the phon'es ability to sit in my trouser/jean pocket with headphones on a bike.