best one to get is the 1.6 petrol or 1.6 diesel imho!

all the other petrols drink fuel like no tomorrow and aren't much quicker, the 1.8 diesel is ok, the 2.0 diesel is quick but hold they're money well whilst the 1.6 diesel will be good on fuel and cheap tax

make sure everything works, older cmaxs have all kinds of electrical gremlins, usually loose connections but time consuming to find.

other than that they drive really well!