If you haven't tried Irwin's bi-metal utility knife blades, I recommend
them. I've found they stay sharp longer and resist bending better than
regular blades. Good stuff. Even better, Irwin wants to give you a
pack of 5 of them for free - go to
www.irwin.com/blueblade and click
the "Get 5 blades free" banner. OK, so I might be a sucker for
advertising gimmicks, but if they want to send me free blades, that's
fine by me.
No affiliation with anyone, I just like quality stuff.
Andy