Does exactly what it said on the tin... plugged into the previously empty slot on my Sangoma A200, downloaded the latest drivers from Sangoma's website, ran the comprehensive installer/compiler which did all the grunt work for me - all I had to do was plug the 12v supply into the card, make up a connection to my phone (the signal appears on the blue/blue-white pair in a standard network socket), and off it went!
Sound quality is excellent, echo cancellation appears to work perfectly (I assume the card is echo-cancelling, it might be Asterisk doing it...).
Lets face it, if you want to plug a POTS telephone into a Sangoma A200, it's not like you've got a lot of choice in the market. But it's good to know that the card is excellent and performs perfectly. It even works perfectly with my 1950s ex-GPO phone.