My friends constantly want to play in my world but now I no longer have the time to keep it open for them. So I'm thinking about transferring it to the new version of Minecraft and buying a realm. All I have to know is if anyone has tried them yet and can tell me if they're reliable on Xbox One.
I bought a realm as soon as 1.2 went live. So far it works exactly as you'd expect. I can log in from the Xbox or from any of my iOS devices, and I can download the world to play offline or upload any of my existing worlds to become the new realm world. I had a beta world that was going OK so I uploaded it to the realm to continue work on it. No problems so far.
I have not yet had my one invited friend join me in the realm, though, and I know there are many bug reports about multiplayer games having problems with clients losing inventory or worlds being reset. I don't know if any of those bug reports are specific to realms though, since technically all players on a realm are "clients" (not host).
I have had a Realms account on Java and on the BTU. The Java version is solid. The BTU has its bugs. I tried it a few weeks before BTU was released to Xbox. Several friends (maybe 4 total?) have joined. I've had 3 on at one time. It works well, but we're seeing crashes on a world that was converted from Xbox One version (and it's a very old map...having roots to the 360 version). So, I think the problems stem from the conversion, not the Realm.
There is one exception...there are occasional errors where I can't connect from my Xbox. I have to do a hard reset of the console and it can connect. But, sometimes if I disconnect again, I have to hard reset yet again. I'm sure that will get sorted out.
Short answer...I'll be keeping my Realm for some time. It's worth it!