I have fairly sensitive skin, so right now I just use some plain old electric clippers for my face and head. That doesn't get very close, though. My whole head has a 5 o'clock shadow type look. The gel thing sounded like a good idea, since it will be like putting lotion or something on at the same time you're shaving. I was wondering where you got the gel replacements.
The mach 3 has crossed my mind, too.
Maybe I should just put some duck tape on my eyebrows and dip my head in some nair.