whats up with the 4200 and 5400 rpm hard drives?

I noticed the powerbooks only have 4200 and 5400 rpm hard drives, are there 3rd party drives that are 7200 rpm that are good and would work fine with the powerbooks? If not, is the slowness noticeable between 7200 and 5400, or 4200?

There is a noticable difference between the 4200/5400 and the 7200. I believe at one time there was an issue of price between the 4200 and the 5400. The 7200 are still more expensive. There is a heat difference between the three drive also, as they get faster, they get hotter.