Since someone else revived this thread, I thought I’d add my recent modfication to my “RestoMod” CX/Gravel bike.
X-shifter is now sold by Cell Cycling https://cell-cycling.com/shop/
I added an “E-Link” actuator and “Mini Pod” shifter to my Cannondale XS800, to shift a SRAM GX10 MTB derailleur on a SunRace 11-42 10sp cassette. $250 total and it got here (CA) from Taiwan in a mere few days.
I did that because I needed something better than the bar end shifter or the old Suntour “butterfly” Commandshifter (modified for 10sp) I had tried previously, paired with the Magura brake levers needed to drive the HS33 hydraulic rim brakes. Front ring shifting is still done with a downtube shifter, since I might shift that maybe once per ride 
So far so good. Setup was pretty simple (once I figured out the phone app), and I have to say that the shifting is more precise than the shifters I had been using previously. I love the fact that it means I can basically run ANY cassette and ANY derailleur with each other. The easily swappable battery on the X-shifter is a nice touch as compared to the Archer batteries I’ve seen. Thought you all might appreciate it. I could see this working EASILY on a TT/Tri bike.
Tom - Glad to hear it’s working out for you! Been somewhat following this for a while, as I think it’d really help out a friend of mine.
Let me explain:
A good friend of mine is in a chair, and thus has to use a handcycle. If you’re not familiar with handcycles, they are… well… what they seem: bicycles for those that cannot use their legs. (Ok… they’re tri-cycles… still…)
Her problem, however, is that if she is powering up a climb, and needs to change gears, she cannot do it on the fly - she needs to stop peddling, remove a hand from the pedals to the shifter, perform the shift, and then get back to peddling.
My thought is something like this as a wireless blip-button on her pedals so that she can do it seemlessly and continue riding (you know, like the rest of us idiots would do).
Do you think this is a system that would work for that? I won’t go into the long diatribe, but essentially she isn’t “allowed” by the government to make too much money, so affording something like this is mostly out of the question; I’d more than likely gift it to her. But I just wanna make sure it works and works well!!
$250 is short change for me, yet enough for her to stress and worry about. If you can get behind it, though, I’d be Ok with gifting her a new shifter… justwant to know that it’s really worth it!
Thanks, Tom!
- Jeff