Hey Gary,
Welcome to the forum. The MX-5050BII should have a switch on the back for IEC EQ. If it's a 7.5 ips/15ips model you should be good to go with the stock solid state repro (studio talk for playback) electronics. If the 5050 is a 3.75 ips/7.5ips model you can convert it to 7.5/15 by getting a service manual and finding the instructions for moving some jumpers or a switch - I can't remember which.
For the Technics, if it's a US model you will need to add IEC EQ in the repro electronics, which you can do with a Seduction modified for IEC EQ and a very simple rewire of the cables coming off the head selector switch. I don't have the specific scoop, but I have heard from a customer who has a 1520 with switchable NAB/IEC EQ, and it may be that the non-US versions of the 1500/1700 machines have IEC EQ. If anyone can confirm this, please let us know.
Regardless of which machine you use, make sure it is in top notch shape mechanically - fresh belts, good pinch wheels, good bearings and good heads.
As for further developments, we do have a more advanced NAB/IEC repro amp design that we demoed in the TAD room at CES with. It's not quite ready for prime time but it will be soon, and it should be able to integrate with a wide range of tape decks by tapping directly off the repro head.
We're also laying plans for an all out assault on a home playback machine, based on the Technics isoloop tape path and our own electronics, repackaged in a more modern looking chassis and with some extra features like IR remote, built in scope, etc.