Jumped onto ATAG and had a blast. The hotfix is spot on. I didn't need to turn off grass etc, only clouds. It was great to be able to fly around enemy planes without any freezes at all. The whole time flying was smooth as.
It's definately on the right track. I reckon they can make the Beta/Alpha patch the official patch now, through Steam.
Won't be long and I'll be seeking an Aussie Squad again and get right into it.