Which mobile radio did you end up getting?
Probably a 2m/70cm dual band rig? Something with a UHF antenna jack, I'd get http://www.diamondantenna.net/mr77.html.
If you want a lip mount over magnetic, I ran http://www.cometantenna.com/amateur-...nts-with-coax/ the CP-5NMO mount, and then I added a dual band antenna that was the height I wanted. Worked great for me for years.
You will have much better results with the mobile than the handheld. Let me know if you have any questions about getting it mounted.