I appreciate your idea on the rear spoiler. My boots have had them removed a long time ago. I have two pairs of boots that I consider current. The first pair are Nordica Beasts, from 2002/3 season if I recall correctly. I had them fitted by Green Mountain Orthotics Lab. during the 2003/4 season, selected from their stock on their recommendation during the fitting. Modifications included a heel lift under my footbeds (custom made for a previous pair of boots), removal of the spoiler, cut down cuff, removed insulation from rear of liner, and a toe lift on the outside of the boot. I can ski these boots, but in general they are too soft and easy to flex too far forward. I usually teach in these. I am mostly comfortable with the fit, but I get some pressure on the inside of my left foot, which makes the area over the bone swell.
The second pair of boots was my idea. I bought Fischer Heat Fire 125s for the 2007/8 season. The boot itself was not a super idea as far as fit, but I wanted to try the SomaFit concept which aligns the sole so that your feet are pointed outward when the skis are straight. I figured that with limited dorsiflexion this would help get a little more effective flexion. I had the back of the cuffs blown out, the tops cut down as low as feasible, including relocating the power strap, replacing it with a Booster strap. I kept the heel lift. The boots were very tight when fit, and I skied them that season only with the thinnest of socks. The following season I could not get the boots to buckle, perhaps because I had gained weight, and perhaps because the boot has restored itself to its original form in the off season. This season I have not had an opportunity to try them again. I was very happy with the service I had gotten from a bootfitter. He did tell me that it was not a good fit for my foot, but I had known that, and I was experimenting. The fit was very precise and gave me a great deal of control. Perhaps the fit was too tight, as I felt very uncomfortable when I skied across some washboard surfaces and everything transmitted very directly to my skeleton.
Further, I have some older boots I could play around with if needed, including two pairs of higher end Dalbello four buckle boots. I want to experiment some more, which is why I was asking the question. I had thought about the Speedmachines and Dragons. I had not thought much about the Salomons. I will put them on my list of boots to consider. I had also been thinking about the Speedmachine 130 and the HR Pro 125.