I think what makes a big difference between it and my old razor (an ?Aquos? 2-blade) was that the Mach 3 has both a pivot for the head and the spring-mount blades. The soothing gel stuff only lasts for 3 or 4 uses, but when its there that helps as well.
I use a Wahl trimmer for my goatee and sideburns.
Here's my question about this:
If placing the blades closer is what reduces irritation (as they say in the commercial), why not simply offer a 3-blade model with closer blades? Why do they need to add any blades?