I went with the Curt with 2 inch shank and use an insert.
I didn’t need the extra capacity of the 2.5 inch shank and figured if I ever went back to a vehicle with a 2 inch receiver, I wouldn’t have to buy a new hitch. Matter of fact, on the Curt’s, if you’re only using the 2 inch ball, i think both the 2 inch shank and 2.5 inch shank have same 10k rating. The 2.5 shank will have an extra 6k capacity on the 2 5/8 ball.