Ive been driving a jeep with a two inch lift and mixed use tires for about 6 years. Folks are correct, those tires will hum and the faster you go, the louder they hum (especially as knobby as those in the picture). You will also feel more of the bumps etc. than in a car or SUV.
I don't really notice the hum or ride much anymore to tell you the truth (until I get in my MDX, then I wonder what part of me actually prefers the jeep, cause it sure ain't my ass!).
I love my jeep and took it on longer trips before the kid and the SUV came along. Nothing like the feeling of cruising with the top off.
850 miles is a long haul, but I'd do it.
BTW, there is definitely a right and wrong way to get the top back on. Do it in the wrong order and you'll wanna kill somebody before you're finished.
You'll notice other jeep drivers giving you a little wave, dunno know what that's all about, but it's a "jeep thing" that you'll see all the time.
Enjoy! :mj06: