I'll weigh in here only because I have the Ultimate ARF and have had DPM experience.
I put mine together last winter and was in the middle of it when I went to the WRAM show and actually met Dave. He was one of the finest gentlemen modelers I have ever encountered. I was explaining to him my experiences with his ARF and he seemed genuinely interested in what I had to say. He also had a prototype of the 330 ARF.
One of the interesting things about the 330 and the Ultimate was that the 330 had the servos in the tail while the Ultimate utilizes a pull-pull. I asked him about that. He mentioned that the 330 was still in development but that the Ultimate greatly benefitted from moving the servos and employing pull-pull. As mentioned above, moving 1oz of servos up to the CG area means 5-6oz's at the nose. By moving 3 servos, push rods, and leads out of the tail of the plane he was able to shave about a pound out of the all up weight!
I am not surprized that he has a work around for moving the servos in the 330. I for one don't have a problem with pull-pull. LOTS of folks do it. One of the other things that Dave had that intrigued me was an odd control horn. It was, as best as I can remember, a crescent-ish moon-ish shaped affair that screwed to the elevator in the normal fashion. The difference was that there was no clevis attached to it. Instead, the end of the cable wrapped over the top of the crescent and attached to the elevator itself. What this meant was that, regardless of the angle of deflection of the elevator, the force was always applied at 90 degrees, thus optimizing torque. Neat idea.

Just so you know that not all is wine and roses, during a flight last summer, my canopy came flying off. Dave attached it to the fuse with 4 screws, two in each side. My guess is that, in the heat of the summer, the canopy distorted a bit, lifting the front of it off the fuse (all the screws were still in and tight when I landed)
allowing enough air underneath. I called Sandy and explained what had happened. From my standpoint it was a design flaw but I had to pay for a new canopy anyhow.