Having played with the controller for a while now, I have to say that I love it. Not perfect, but its a superb start.
I managed to complete a full FTL game with complete ease, forgetting that I was even using the controller. Which in my eyes is great praise.
I also got through a fair bit of Portal Stories Mel with it too. Had to make some tricky portal placements which would have been easier with the mouse but I still managed alright.
Got it up and running with Elite too. Not sure how truly playable it is but its certainly more customisable and better than Xbox 360 one. Guess I'm just too used to my X52 Pro
Negatives of controller - feels cheaper than Xbox/dualshock. Extended thumbstick use had my thumb hurting, its a bit too low. My right trigger can sometimes become a bit rattly as it moves the bumper above it. Doesn't happen much but its a bit annoying.
Overall though I'm super happy with it. Just wish in home streaming was a bit more reliable, too many times I have to pop upstairs to fix something on the computer (also elite seems to be crashing. Now sure if its streaming or the game. May need driver update). The actual streaming is awesome when it works though, I stream on to my surface and game on the sofa while the gf is watching TV. (I did buy pretty expensive router though to get it working so smoothly, was not so great over WiFi before)