I found the side XMR.TO some time ago and found it to be a good way to exchange XMR to BTC and keep the privacy XMR offers. I gave it a try twice (small ammount of XMR). The exchange XMR -> BTC went flawless and instant.
Any more reviews about them?
I've used them a couple of times to get BTC, I think that rates are just a tiny bit better than shapeshift, but you get your orders sent out instantly if it's below 0.1 BTC per order. When I used them, the transactions were pretty much all instant as well.
Not sure how much you can trust them with higher amounts but looking at everyone else's feedback, it's going to be alright.
It's a great initiative... It essentially preserves your privacy and extends the functionality of bitcoin. Honestly, it's much more simpler to use than most other exchanges. If you are doing xmr to BTC transactions, use them.