I have several Mothers foam core drying towels as well and like them a lot too. As said above, you can do an entire vehicle. You can wring it out but I try to be careful not to twist it too much since it is really sandwich construction.
When I towel dry, I typically blot dry the horizontal surfaces, try to remember to do the windows second, and then do a general wipe down after the towel is damp from the blotting and doing the windows.
I also like the Mothers 20 x 24 towel. It is a perfect size between the typical 16x20 and larger 24x36 towels. It is very manageable when wet.