I tried beaker when it first featured on HN. My website isn't particularly heavy. It completely crashed the client trying to upload it. We're talking < 100mb of data. I believe they're still working on the issue [1].
The next major release of Beaker (0.9) is going to have a new version of Dat that improves scaling quite a bit. Mafintosh and his team has done some amazing work using trie indexes for much faster reads across the network. Beaker's also gotten much better at syncing with folders, which was the issue in your link.
Beaker didn't run on my Ubuntu. I opened an issue and was ignored.
I guess Dat is too much JavaScript to be worth it anyway. The tooling and documentation are very poor, most of stuff is outdated. They claim to have a vibrant community but it's mostly two or three guys loving their Beaker browser and caring none about the rest of the world. Perfectly fine for a closed community, but not for a protocol that should be aiming widespread adoption.
[1] https://github.com/beakerbrowser/beaker/issues/952