WOW. The 64 bits definitely adds to the stability of the program. The only issue I had was that flying at night the lower half of the screen would go black. Starting at the controls in the plane it was like a curtain dropping. Lasts for about 30 - 45 secs the goes away and repeats. I did not see this issue during daytime flights.
I hope SLI is in the works for this program. This will be the FS of my choice.