Perhaps I'm wrong, but I don't believe there is any future for a 70cm 56kb radio in the ham market.
- Brian
I think you're wrong. Well, actually, I know it! ;-)
Very few, if any, hams that I know would have any interest in the kit you mentioned. Including me. Far too much work. Too costly. Far too complicated for the average one-day ham-cram technician-class, appliance operator ham. So even if a few might be willing to do the work to put those at the "server" location(s), you won't have many/any? "clients".
In contrast, we've had about 30 or so folks waiting for an appliance-like device, such as the NWD UDRX. Probably more over time. And that's just ones that I know about in this one county. Why? Because it would provide a practical solution to a very real problem - how to get modern messaging connectivity for the appliance-operator ham. Because their price-point was about the price of a dual-band mobile - very reasonable. And because, as I mentioned earlier, faster/higher frequency just isn't an option for most of those people due to line of sight problems.
Michael N6MEF