That's true. I'd say, probably performance is the first trade-off, weighing kernel against user-space. For the sorts of scenarios I envision for Tela, it's probably not a huge loss (I won't be running Facebook off of a Tela hub, I don't think). Another is that I have to run and tear down the client myself, though I do have support for running the tela client as a service.

It's funny... I've started using so many of the nifty management features of TelaVisor and Awan Saya that I am now considering adding lower-level support for the features that I explicitly wrote for user-space.