I did some testing with 2 openhab versions to one ethernet gateway. At first it did not discover any devices, thats because they were allready discovered in the old (2.5) version of openhab, I Think, because when I created a new mysensor device,it was immediattely discovered by the new openhab. I noticed a minor problem, there is an ability to scan (and because auto discovery did not seem to work I tried this), but after a scan the ethernet gateways failes. When you try to add a device(manually), it goes back to the first page when you select the gateway. I had to restart de openhab service to get it running again.
I tested with a new blinds sensor (with smartsleep), and smartsleep seem to work OK. So I prefer this binding over de generic mqtt binding, because stuf like request() and smartsleep() work 'out of the box'. These are my fisrt tests, I will be doing more (other sensor types) later on when I have an additional gateway available.