If you are ready for Medicare yet, then SD may not be the best place for you because you will have very limited plans for individual health insurance, most of which will require you to be in the state for extended periods of time.
The last two items on Dennis's list are really not that much of a problem is you choose Texas. You only do the safety inspections if you are in the state - - we know people who have gone ~ 5 yrs between inspections. As to the special driving licenses - if you have a rig weighing more than 26,0003 and you can't pass the test, you have no business driving it on the road.
Barb