Glenn,

I consider my buggy to be a true dual sport car, since I drive it on the freeways, in the desert, and everywhere in between. It's definately true dual sport in that it does well on pavement and off road, but doesn't do as well as cars specifically set up for those purposes. I chose to go with an IRS pan because of its superior handling characteristics. I think king pin and ball joint front ends handle about the same on the road. The main difference is that the king pin front end is more durable and easily lends itself to long travel mods, where the ball joint front end does not.

Having said that, the ball joint front end seems to be pretty durable for recreational use, as long as you have stops to keep the ball joints from over-extending. If you don't intend to drive in an aggressive manner, the ball joint front end should work just fine.

If you really want the king pin front end, you will have to decide which end of the car you want to perform surgery on (like you said). I have only witnessed an IRS conversion, so I couldn't tell you how difficult it is to swap frame heads. I do know that the IRS conversion was very difficult! Let's see what everyone else has to say!
Lee
Tustin, CA