About 6 months ago I stopped using SM and moved on to nolimits. I loved all of the features of SM, but it was incredibly slow. Most coasters would run around 20 fps, but in nolimits I got usually 60 to 100 fps. I had even tried to set every setting to the lowest, but still I never got over 30 fps. After update 1.55 I tried turning the settings from high to medium, and suddenly SM was running around 450 fps average! I am gladly willing to sacrifice some detail to run the game 15 times faster. I may now go back to making SM rides. I've got lots of cool car type ideas for the invisible track: hanglider, sled, car, etc if I can ever get them to work.