Yes, very good towing vehicle... But I am biased
check out The Truck Stop
for a great community of folks that can help the 6.5TD to its full potential.
The biggest issue is the PMD, which is a GM design flaw. Once the PMD is removed from the IP and relocated to the front bumper area they are a very reliable engine. Keep your grounds clean as well.
After the normal preventive maintenance, I recommend a better turbo and exhaust as the stock system is very restrictive. The result is more power and less stress on the engine resulting in lower EGTs.
Feel free to PM me if you have any 6.5 questions!