Thanks for the kind comments.
Had the opportunity to run this buggy over the weekend. First time out the car performed very poorly - it was erratic at best. I suspected that the poor performance was caused by unsuitable rear tires and a rear diff that needed a rebuild.
Swapped out the tires for some bowties and rebuilt the diff for the next run. Performance was much improved. After some spring tuning the car started to find its groove slowly... actually keeping up with some of the 1/8s going around the track. It lost out on the straights due to the stock class motor but through the turns it was doing quite well.
It drives very different from a standard 2wd through. On power it seems to understeer but off power the car brings its rear around quite well. I had to watch the throttle at lower speeds as the rear had a tendency to come loose if I pinned the throttle too hard. At higher speeds though, it seemed to be a lot more stable around the track.
I was browsing the X-6 forums and was glad to read the experiences of the X-6 drivers. Although I'm sure my car performs nowhere near the level of the X-factory buggy, the descriptions of their buggy driving characteristics seemed similar to mine.
What are the other mid motor guys experiencing?
More tuning to do to try to get more steering on power... I probably need to fashion a way to adjust roll-center in the rear.