Now, if I'm careful, I can make a extremely good pork loin just on the pellet grill... but yes, I agree, that probably the best use for Sous Vide, is on bigger hunks of meat where, overcooking is too easy to do on most other methods.
If you haven't, a great way to do things , is to smoke the pork loin first, just for a short period if time at relatively low temperature, then either cool it down just enough to vacuum seal it , and then finish it Sous Vide .... or smoke first for short time, then cool it fully, vacuum seal it , and sous vide on another day.
But yeah, I would say the best reason I could think of to do Sous Vide, is on something like roasts, pork loins, boneless chicken breasts, etc... with pork and chicken being the most value, because they are so easy to overcook using normal methods. Beef tends to be so forgiving, that I can usually manage to cook it without too much need for Sous Vide.
Believe it or not, veggies are also GREAT when done sous vide, you don't loose any flavor to them soaking in boiling water, etc...
