As already mentioned Tom Pro or King. I used to own a Short Sandcar and I kept breaking it. Not knocking Larry's work, I just feel my driving style was more aggressive than anyone else that has owned one because I broke things nobody else did. I busted many spindles, a rear hub carrier, and a few frames as a result of the spindle failures. I finally had him built a custom car to my specs: http://www.dumontduneriders.com/ssc_buildup.html
and it did great! http://www.dumontduneriders.com/ssc-perf-review.html
That last Busa SSC car was dialed in great and the only reason I ended up selling it was because I still wanted to step it up to the next level and that was a full size turbo Honda car. I saw the Tech 3 turbo Honda for sale and had to have it. It had better suspension, front brakes, reverse, better charging (an alternator), it was a bit safer and heavier to soak things up and it had alot more power.
Busa cars are a blast to drive. It all boils down to your driving style.
If I were to buy a Busa car again I think it would be a King. Brian (the owner) is a duner himself and those guys rail out there. I've seen them in the dunes and they drive pretty similar to our group.