We bought a 3 year old F250 fleet lease return with 100K miles on it and saved as much as $40K over new. Enough to buy another TT if we wanted. :) We use it mostly for towing and it gets maybe 5K miles on it a year and will outlive me at that rate. Has the V10 and 4.10 gears which are great. Four years later, it's running great. We used to tow a shorter TT with an F150 and would never go back now.
If you don't need it for a daily driver and won't be putting a lot of miles on it, I would say pre-owned makes sense. Unless you absolutely need it, don't get 4WD. It takes away payload capacity, costs more to maintain and is about 1/2 foot higher off the ground and costs less up front. A 3/4 ton is simply so much more capable and better handling. Try one out!
Oh, and black may look really badass, but it's impossible to keep clean. :M