I guess it depends on what you mean by "do as well". For just 20m and above, either will work fine, although the screwdiver should be more efficient. Once you start going to 40m & 80m though you're going to have some work to do to get that tuner working well with the whip. Both a radio buddy & I have jeeps. He went the 102"/tuner route and I went the full size screwdriver route. He spent a ton of time trying to get it to load up on 40/80m, but the actuall mechanical aspects of the install are easy. I spent a bunch of time trying to figure out how make the screwdriver be structurally sound but once I did that, getting it to work properly on all bands was easy.
BTW, the LDG tuner is probably the wrong one for that job. I think you need to look at SGC's offerings. Anyway, to get the 102" whip to work with a tuner on the lower bands, you're going to need to use quite a bit of wire to get a suitable match. You can't use coax. SGC has a chart that shows approximate lengths of wire at:
Selecting Wire Length. You'll see that you may need as much as 50' of wire. Another problem to seriously consider is that you will have a lot of voltage on that wire. If you're thinking about putting a 500watt amp in there at some point, you could have 10,000 volts at the output of that tuner! Also, because of that voltage, you can't use the cheap ball mount for you whip anymore...they won't handle it!
I didn't want to deal with all that, so I just got a Hi-Q. Now, there are all kinds of automatic screwdriver controllers, which makes it almost pain free. You have to figure out how to mount those heavy antennas, though.
