I use 2 different ones.
On one car I have a Larsen on-glass. It doesn't work as well on 2 as a NuTronics 6db colinear, but it works pretty well. I consistently get about 40 miles to a pretty high repeater site on either band. (And it works pretty well as a scanner antenna - even on 39 MHz, which surprised me.)
In the other car I keep a mag mount of pretty much the same antenna - a Larsen 2/70.
I haven't been unhappy with either of them, and I've had them both for at least 15 years.