It would help to know what frequencies you want to listen to, strong or weak signal area, what of vehicle, any restrictions on the mount type... you get the idea. There are many threads already running in the forums. Take a look and give search a try. HTH.
Best advice I can think of is an antenna made for the frequency/band of choice, and one that's mechanically able to withstand whatever may happen to it in normal use. A bit vague? Sorry, but it answers the question asked.