I've been running 2009 and 2009 on a MacBook Pro 17", 2.16 core duo, 2 GB Ram and x1600. This computer is about 5 years old and it runs 2006 without problems with the sliders maxed, 2009 I have to used windowed mode and sliders at normal, but I get around 30-40 FPS with it.
As far as which is better, that is personal taste. MSTS and Trainz are about the only games I have loaded. My main program is Final Cut Studio. For me a computer is just a tool. I find what I like to do the most outside of train sims, Macs work the best for "ME".
It's not so much Mac won me over but Windows lost me. I know what it takes to maintain a Windows system. I also know I have no desire to spend that time doing it. With so many variations in Windows boxes, along with security issues, I decided enough is enough and switched. I use a computer for my hobbies, not as a hobby in itself. I want to edit video or process pictures, that is what I want to do, not have to fool with the OS just to get to that point.
Aside from my MacBook Pro, I have a PowerMac G5 2.0 dual that has been running non-stop since I bought it new. It doubles as a T.V. with my 30" monitor. I also have an iMac G3 that I bought new in 2001. I use it for all my Blender mistakes and some photo editing. I love the screen on it for color balancing and printing.
Are they "better" than a PC? Not really, parts wise. OS wise, for me yes. I can't complain since every Mac I ever bought is still in use with me and really see no reason to upgrade any of them. Much more than I can say for the several PC's sitting out in my shed. I paid a premium for my G3 10 years ago, along with the others. 10 years is a long time to be actually using it still. A good value in my opinion. Same thing with my 5 year old laptop. Still going strong. I will upgrade all my trash eventually, just see no reason to do it now since most programs I have are optimized for the systems I have.
I'll buy the Mac version of Trainz and try it out. If it runs, great, if not, I'll shelve it and stay with 2006. I won't buy a new computer just to run a game.
Dave.......