I have the free Blue Cat chorus, along with perhaps a dozen other chorus plugins. It's not bad, but on vocals in particular nothing I have beats the old Kjaerhus Classic Chorus. I use it a lot. I wouldn't be concerned about it being unsupported - I mean, it already does what it does and isn't going to suddenly stop doing it just because the developer has dropped off the face of the earth.
Two other favorites of mine are the free TAL-Chorus and ValhallaDSP's Ubermod. The TAL Chorus is nice for that classic Roland chorus effect on synths and rhythm guitars. Ubermod is just plain fun, as you never know quite what to expect.
Don't forget to try the Sonitus Modulator's ensemble mode. With a subtle mix level of 10-30% it can be nice on synth pads and strings, although I have to admit I've not tried it on vocals.