I'm running one. It seems totally fine, and I'd really strongly recommend doing it. Remember you have to leave a tab open for it to work. The website doesn't emphasise this enough, in my view. If you simply pin the tab, it'll be (a) very persistent and hard to accidentally close, and (b) totally inconspicuous, so I recommend doing that.

I'd also strongly recommend running a full Tor node. The best way we can support Tor is to flood the zone with proxies, so it's no longer possible for intelligence agencies to control quora of Tor entry and exit nodes, as they very likely do. If you live in the developed world and have a good internet connection, I think it's a civic duty to redistribute your bandwidth - to socialise the means of conduction.

Edit: 'Quora' was probably a poor choice of word, since a quorum implies consensus between nodes, as in a distributed system. It's really about intelligence agencies controlling _majorities_ of nodes - or even a large number - so as to make it more statistically likely that any given Tor circuit will begin and end with a node under one's control.