I got 12K out of my original Dunlop. I replaced it with a Michelin Commander II Rear Tire mounted in reverse on my 2012. I did that on a previous trike and it lasted a LONG time. Never wore it out, traded for a 2012.

 

I'm probably going to have to replace my front at 8,000 miles. Did a lot of riding in twisties in Oregon. Coming out of turns hard the front would slide a tad. Guess that did it in. Probably going for the Michelin Comander II.

FWIW...I care more about handling than life. You could put a tire on the is made out of hockey puck rubber, and it would last forever. Wouldn't handle for **** though. There are many things that contribute to tire life and handling & traction. And I am sure there is a cross over point where higher life impacts handling.

 

The problem with the superior handling motorcycle tires on the Trike is that you only use the center portion of the tread. The great handling comes on the sides of the tires for motorcycles. That is the reason for the newer multi compound tires. The Trike never gets to the softer rubber.
If you get a nice handling compound in the center, it might help with the sliding, but lose in the millage dept.