There are zero and none benefits disabling AERO. Its just the opposite.
With AERO OFF, you instruct the computer to use the CPU running all graphic instead of using the GPU-chip onboard on the graphic card. You also make the computer and system/Cubase fail on all direct graphical API calls.
Secondly, the old Windows 95 theme looks ugly as hell too. Thanks Ed for making this helpful thread sticky. 
Best Regards
Freddie