Yeah I've been flying on it for a while now. There is quite a good community around it in the UK and Ireland but the NI sector of Scottish control and the airports here are not routinely staffed with ATC although there are events now and again. The Irish division of VATSIM is called VATEIR and whilst their forum is quite focussed on flightsiming and controlling it is broader than that - not unlike an ROI equivalent of this site.
Flightsiming online is a good way of getting to know the airways, waypoints and the STARs and SIDs which the airlines are flying in the real world. It can be challenging and enjoyable but the controllers can be quite unforgiving sometimes if you mess up!
I have FSX which is great but the more you increase the graphic and other settings the slower the frame rates go. A lot of people still use FS2004 because of this. Microsoft pulled the plug on the division responsible for FS development but there are still lots of add-ons hitting the market from other providers.
