How cool would it be to have a simple closed loop servo drive for your encoder gear motors. I can't imagine how many more applications can be accomplished with this type of product. I currently am using many of your encoder gear motors for projects, however I have to jump through hoops to purchase a driver that was designed many years ago but works flawlessly, but hard to get. This would be a great addition to your product line. Here is a link to what I am currently using. Try finding something that even comes close on the world wide web. You should be making this....
People could be using closed loop servo instead of steppers for so many projects and simply use the same step and direction source they are currently using, but have a close loop system instead. Jeez, how hard could this be for an outfit as talented as you. Your jk drives come close, but not quite the same thing.
You can do it Pololu, and I will bank on a HUGE success for this product. Just reading your forum, and others, so many people would benefit from something cost effective like this!!!!!
Like Nike says, Just Do It. You might be surprised.
P.S. Here is a video of your encoder gear motors being used in a vending machine project using position servo drives.
And another showing simple position control again using your encoder gear motors.