I've got an 05 Excursion with the V10. Great low end torque, smooth running, moves the Excursion around nicely around town, towing, and climbing long steep grades. I'm happy with it. The 6.0 is quite a bit more powerful once it gets spooled up, but it is gutless until the turbo spools.
My brother has an F250 with the 6.0. On a snow packed road sinking in about 4 inches, trying to turn around, he had no power. He would floor it and it would make a funny growl, wouldn't move, wouldn't break traction. He could barely get it moving in low range. I loved the 6.0 on the highway when the turbo is spooled, but once I saw this, it was V10 for me. I plan to use the Excursion off-road later in its life and the 6.0 clearly is not up to the task.
A buddy of mine has an 06 F250 with the 6.0. Again, great power once the turbo spools, but on a cold morning hooked to a trailer, the thing can hardly get rolling. If feels like you could stop the truck with your hand on the grill it's so gutless off the line when it's cold. It's a little better after letting the engine warm up a long time, but it's still pretty gutless even then.
You get better mileage with the 6.0 than the 6.8 V10. The V10 gets around 12 mpg in the Excursion, the 6.0 seems to get around 18 to 20 in the trucks.
Depends on what's important to you. For me, it was low end torque. Around town, pulling away from stop signs, the V10 moves the heavy Excursion effortlessly with 3.73s. I pulled a Blazer on a car trailer halfway across the country and over the passes through Colorado. Pulled great. 65 to 70 up the steepest parts. The engine puts out great torque off the line, then it seems to hit another band of power around 3100 to 4500 rpm so it also has decent top end as well.
If you put the V10 vs. the 6.0 in a towing contest up the passes, the 6.0 wins hands down. My buddy pulls his skid steer in a dump trailer half full of dirt up the passes and the power is unreal. But how heavy are you towing, how steep, and how fast do you need to go? Towing 5000lbs up the passes at 65 is fine for me.
It's quiet and no diesel stink keeps the wife happy. She drives the vehicles when still pretty new. I get 'em once they become the family camping rig/beater.