Todd, the '07's are the beginning of the good/usable trucks. I had a '06 DC w/ 4.7L that I used for work and to pull my 25' travel trailer (6000 lbs loaded)...it did ok, but not as good as a '07 with a 5.7L would do! A few months ago I traded it for a '07 2500 Ram QC Hemi and love the truck...WAY better performance and stability over the '06 Tundra! Still want a Cummins, but it simply didn't fit the budget!
Best of luck with the sales and purchases!!