Awesome. I think I will try a couple and see how they do. Chilling hours are readily available for <45 in my area but I don't see anywhere listing sub 40.
My area gets anywhere from 400 at the lowest to 800-1000 chill hours average a year and summers can hit 115.

Thanks for the input, I may reach out to you again in spring. I have several species planned already and this one may get cut to make room for cherimoya or something else.

Where is it available now ?

Stewart is much better than mexicola.  You really should start seeds there and then get scionwood from someone here and have a grafted tree true to type.  Then you can do whatever you want with it, use scions or seeds to sell and propogate. 

If it was me I'd go with Duke or Stewart which are very cold hardy pure Mexican race varieties.   Texas friend recently got some Duke fruit from his SoCal friend and loved it.  Said it was nutty and in spite of the ultra thin skin said he had no problem spooning out the meat.  Makes a great rootstock somewhat resistant to Phytophthora.

Try here.
http://tropicalfruitforum.com/index.php?board=2.0

Good luck!

A very promising cold  hardy hybrid  produced by B.Voss in Hamburg.
It is believed to have C.ichangensis  and Poncirus as parents. Leaves are mostly monofoliate and that is why I think that  the story is more complex, could be citrumeloxichangesnsis. 
My plant is now more than 2 m high, planted in 2012, never protected, never damaged.
Dozens of rather large pear-sharpen fruits.



Skin is pleasantly lemon-like, although not strongly scented, albedo is moderately bitter, no poncirus taste or odor.
Around 20 large, ichangensis-like seeds.



Moderately juicy, less bitter than grapefruit, rather acid, but less than lemon.
Some fruity aftertaste is faintly present, but is is very different from poncirus.
Amazingly, at this stage the juice already contains  a lot of sugar: 11.5° of Brix, approximately the same as commercial clementines.