I used to cut 50-100 boxes a day. An Olfa L yellow handle utility knife and a box of 50 xtra-sharp blades ( the black ones) will outcut any folder. One blade lasted me 2 days. All my other regular folding knives packed it in before lunch. It's the wafer thin blade that makes the difference , plus you can snap off blades to get a new tip/edge.
http://www.uline.ca/images/product/Large/H_711_L.jpg ( knife)
Yep. You're absolutely right.
Honestly, the good old Olfa is probably the best choice out there for pure cutting tasks. I like fancy knives, and I get good use out of the ones I have, but they all crap out when you have to cut fibreglass insulation, score drywall, cut acousitc ceiling tiles, open bags of quikrete... a sturdy snap-off knife is really the only choice when you have to cut things like that, if for no other reason than because you are able to replace the blade instantly when it gets dull. I don't care what supersteel a knife is made of, difficult cutting tasks will turn it into nothing more than a really expensive butterknife.
Now, I get the feeling that OP is looking for something with a little more cool-factor than an Olfa, and that's easy to accomodate, too. I used my folders instead of box cutters when I used to work nights at a warehouse, cutting and breaking down cardboard boxes all night. A lot of them stand up to a day or two's worth of that work just fine (the ones I had in 13c26 seemed to hold up fine for one or two shifts, for example), but some of the poorer steels do crap out pretty quickly (440a, 420HC, and 8cr13MoV for example).
If you want a knife that's got neat features but can still hold up to a day's work, I'd avoid the Tenacious, Scallion, Buck 110, etc. - They might be good knives, but in my experience, the steels they use are really not up to doing large quantities of cutting. There are plenty of knives with decent steels that aren't too expensive, though - I'd check out Kershaw knives with 14c28, like the RAM, Blur, Skyline, etc. Goosey's recommendation of the Delica in VG10 would be a solid choice, too.