I sat back and watched the responses trickle in. Both to this thread, and to the other one posted about the TT itself. Clearly the consensus, (nearly unanimous) was that you'd be unhappy with the 1500 and would be much better off in the long run with a 2500. I have to agree based on all the arguments offered so far. I think the REAL question is, were you really looking for advice, or just hoping for a confirmation of the decision that you've already made.
My son decided to buy a Silverado 1500 to pull their new horse trailer. Even though it was spec'd sufficient to pull the weight, (gooseneck), and the suspension was spec'd to handle the weight in the bed, both were fairly close to the limits. My advice was to go with a 2500. He wasn't really asking for my advice, it turns out. What he wanted was for me to put my "rubber stamp" of approval on his decision to buy the 1500. Of course he did, and now that he's had it a little while, he's already shopping for a heavier duty truck. Of course, his "cover story" is that he's planning to upgrade his trailer in the future, and will need a heavier truck for that use. As all you guys out there surely know, it would violate a code if a son ever admits that his father was right. The only exception is when one of the two is deathly ill. In that case, the admission can be made, but only quietly in private. Of course, both father and son must understand that this confession is protected confidential information, which can never be shared with anyone else.