It may seem like a lot but its really a bareable performance, but yes I prefer five blades. Some of the best things on razors out there that I have personally tried are the following:
Vest pocket Razor blades
Incredibly safe to perform ie uses dull blades. But just like a smash and stab there is room for human error.
Tim ellis's razor blade routine
Safer and requires no stands or holders, and I really like the way he makes the blades Safe, yet be able to cut card stock.
The more dangerous but equally as effective blade routines:
Mug ditch
Blades hidden in plain sight
Both taught on
"Helter shelter" Bizzaro and no those aren't technical terms but its how I remember them. Bizarro uses sharp blades in both, but I do not recommend doing that if you are new. Also personally I would purchase Bizzaro's DVD and Ellis's routine. The more ways you know how to do an effect the more of a guerrilla platform performer you will be.
Then of course there are the stands and what not you can buy, but I do not see the point in them.