N5BOC has a Tindie store setup to sell his MMDVM boards for those of you interested in building Pi-Star hotspots. N5BOC, David Dennis, has designed these high quality boards from the ground up and they are of much better than the stuff that's being imported from China which can have poorly constructed RF blocks.
David has the boards made in small batches so if something is listed as being out of stock he usually has some more in a short period of time. I believe you can sign up for an alert email if this is the case. They are popular. These modems do cost a little more than their imported counterparts, but if you were to do a side by side comparison, it is easy to understand why. Product support is also very good.
I have personally constructed hotspots using both the simplex and duplex versions and have been very pleased.
N5BOC's Tindie store, (Lone Star Electronics), can be found here:
https://www.tindie.com/stores/n5boc/
Thanks Chris. It's great that we are getting down to the details of choosing the MMDVM boards based on quality criteria instead of just treating them as commodities. Now we have some facts to guide our decision making.