Mike's memory is off. (Believe me, I understand; I'm even older than he is!) I first gave him the specs in an email dated 4/26/2009, and I've repeated them to him once or twice since then. It's his decision when or whether to produce a suitable design; when he's ready I'll naturally work with him - we've collaborated on these things before and it's been pretty fruitful as well as a lot of fun.
Normally with a new Bottlehead product, Mike waits until there is a large enough customer base to justify creating a design and manufacturing a run. So the best approach is to convince him there are interested parties. You can ping him by email or (better) telephone, or even start a thread on his forum.
As for sonic quality, I expect that with steel cores Mike's design would have similar extension (bass and treble) but would be a little better musically than mine, due to his better materials and workmanship, and because he would make a design specifically for the target application. But I can't get nickel cores from our transformer house even if I wanted to; they are too fragile for reliable machine assembly. And Mike has more experience than practically anyone with nickel cores. I don't have a personal Stereomour yet myself, but I'll manage to make it happen once Mike has some iron to put into it!
