It's a good concept, if a little bulky right now. I think it might be possible to shrink the parallelogram arms to about the same size as the old Softride stem had. What worked for them should work for you. Both stems are subject to the same stresses. In fact, it may be necessary, at least from a marketing standpoint. One concern is that the wide stem with the relatively sharp corners would be a safety hazard. Stem manufacturers always boast about how their stem can't bash your knees. Use the Softride width with a single gas piston in the middle. To make space for the piston, increase the distance between the upper and lower arms. It should be possible to do this without increasing the height of the steerer clamp by offsetting the pivots forward of the clamp and the upper pivot upward. It still looks a little overbuilt. Like any good component, it could stand a good FEA analysis. I think the upper arm can be made of something lighter since it's only in tension (and some torsion), not compression.

Also, make the description more focused since people seem to be getting confused. Like HappyStuffing above, some seem to think this is only good for finding an "ideal" handlebar height. You need to let people know that this is for changing riding position on the fly just like using multiple hand positions on drop bars or on flat bars with bar ends, but keeping the brake and shift levers always at hand no matter where the handlebars are. That's a disadvantage of bar-ends or even trekking handlebars, where only the main hand position has access to the controls. Over the years, various companies have made right angle brake levers and lever extensions to allow braking from the bar-ends, but those never helped with the shift levers. Finally, at $275, the market would be very limited. Get it down to somewhere between $100 and $150, about the same price as what the Softride stem retailed for. I know I've considered buying a Softride on eBay over the last few years, although bushing wear has always been a concern, especially since the Softride is out of production so it's impossible to get spare parts. Maybe design the stem around Garlock DU bushings in one of their standard catalog sizes.