I've only got good things to say about ED Tracker and my interactions with the guys there.
I bought mine last December just after getting ED, a cased 9150. When I bought it I could see it was a hobby shop bunch of guys making these things, using arduino boards. I was happy to pay them to build it and ship it rather than having to ham fistedly solder it myself. It worked on delivery, in fact the only issue I've had was when I didn't keep the software updated and a call for help on these forums had the ED Tracker guys pointing me in the right direction very quickly.
Yes it's a product and yes its not perfect, but I do think they are pretty clear what you are buying, and the level of 'professionalism' is fine imho, in fact it far exceeds the level I've experienced from much larger organisations.
I made sure to tape the USB cable to relieve the stress on the connection when I attached it to my headset, it's been 100% reliable.
It's always annoying when something breaks and if the response you got wasn't an example of them at their best then as far as I know it's the only example I've heard of and they do seem to have rectified the issue.