Okay I have been on the vox atc for 3 days now. Seems pretty solid. have used sid and stars. it seems to work nice with my payware feel there erj145 and my 737 ngx. Works with my navigraph cycles. Cant really complain, yeah its not perfect and sometimes you need to repeat yourself but its seldom unless you have had to many beers and start slurring your words.
So if you decide to do any flying away from vatsim I highly recommend this software. It is definitely going on my must have shelf.