I would be geniunely interested to know if anyone has used VatSim (real people providing ATC service). I was thinking of joining up to practice RT but I don't really know if it's any good,
I've got a buddy (whos actually in the middle of his NATS training at the moment) who gave it a try. He said there were some real world controllers (or so they said) but the majority of them were a bunch of kids that thought they knew everything about ATC.
When I was practising my RT I used to visit my local airport/airfield and have a listen in. Was good fun to see it all happen.