Every Dodge the ex had, was good ones. Never a bit of trouble. His V8's got way better gas miledge than my Trac. If there were no F150's or Sport Tracs I'd go with Dodge. As for the lift shop, they are only one shop, Maybe it's because the want to only do the easy lifts and not take the extra time that would be needed because of the IRS. That's what they do, Not what they make. Sounds to me like They only want to customize what they can. Maybe the are not prepared to do a lift with this new Trac. As it would take a bit more effort. I was told it could be done, but would cost more and take more effort True IRS screws up doing a "normal/easier" lift. But it can be done. I bet the Lift kit companies have something in the works for the Newer Version of Sport trac. You could always email those companies direct and ASK them. Tell them what you want and ask them when they expect to come out with a kit for your truck.
I guarantee you if it can be done somebody is going to do it. Don't get discouraged. Heck take a look at the Tonka Trac. I was amazed at that lift. I'm sure others never dreamed of a lift and wheels like that on an ST and it is an early model, the point is: never say never.