Yes, TS2009 with TS2010 is a very stable & unique program. You need to configure your browser to allow all .exe files to access the Internet through the firewall.
All versions of Trainz have well suited the Trainz Community, progressing to the latest build has always been a challenge to take it further into the unknown.
After all is said & done, it always has come down to the end user & how much they know about computers in general first...
So far I've found TS09 marginally more stable than TS10, but I'm running them on differrent machines, so it's not a fair test. TRS04 is next most stable for me with TRS06 last (of the versions I've used).
I've rarely had a problem with TS10 in months, no fatal errors, only issues i've had are down to the user.. most stable version definitely Its a pleasure to use.
I'm running three versions of trainz at the moment.
TC3 and 06 no problems whatsoever, in fact 06 has been excellent since the server changes.
2010, hopeless, but it must be my pc specs as others swear by it, rather than at it.
I've had a superb run out of 06 since installing 06 SP1 4+ years ago. (my TRS2006 directory size is well over 300 gigs)... As much as I love 06, I've personally found TS2010 to be far more polished. I particularly like CMP 3.3 over CMP 2.6. Currently spending 25/75 between the two... (2010 - 75%)
I do not have 2010, but I have found 2009 to be very stable, more so than 2006. A lot is dependent on your computer specs and the way it is configured.