I have not played with the Manger drivers but have looked at them occasionally.
I try to prioritize my development efforts based on the expressed needs of customers. For example, I am presently working on a new Veracity model. It will be an MTM design using a pair of regular Seas W18's (as opposed to the W18EX used in other Veracity designs) and the new LCY tweeter (which, among other things, will allow for closer W18 spacing).
This was based on an order from a customer who needed three sealed speakers for his home theater system. In the process, we are developing both a sealed and a floor-standing ported version of this speaker.
Another recent request we may pursue shortly is a dipole/monopole surround speaker.
Naturally, if anyone is interested in developing a speaker for the Manger driver, I'm all ears