Don't bother. The complimentary comments are posted by the person who made the ad, using different accounts, I think. If it works at all, it is just a registry cleaner. Although they're useful, they don't speed it up much.
You won't notice the difference in speed.
You'll get a far greater speed increase by:
Defragmenting your hard drive;
Checking your disk (CHKDSK or the built-in Windows equivalent)
Adding more memory
Getting a faster graphics card
Most other things won't make any difference that you'll ever notice.