Having owned Dynaking, Renzetti, Regal, HMH, Snowbee waldron, Griffins, Anvil, Danvise, and a boat load of cheapies I think I can at least speak from Experience, rather then A friend heard it was junk kind of thing..
I know at least a couple here have had one generation or another of Norlander's vise, I've yet to see anyone post specific details to support the bad mouthing. Comparing current production with early models is kind of silly. Fit and finish is on par with most other vises, and from the vises I've owned only HMH was a clear cut above the rest. I've not had to use any kind of support on the Nor-vise but from what i've heard it is no problem, and you can expect great service as long as Norlander is around.
Functionality, like some other vises it is a bit fussy on setting the jaws properly, once set it will hold most any hook, the optional jaws are nice but not required (much like many other vises). I own every optional Jaw set and it does make for a nicer tying experience. As for what the Nor-vise can do that others cannot, not much, maybe a couple very specific dubbing techniques. However using the vise properly can and will speed up production tying.
Portability Anyone who says the vise is to big, bulky, not portable has obviously not used it to any extent. First point, C clamps are readily available if you don't like the board system. The small board Norm sells as a travel board is perfect. The size is just right, it is light, and easily moved with one hand. I can kick back in my lazy-boy and tye no problem, this is the only Vise i've had that can do this with ease. I can pick it up off the table and move it anywhere, much less effort then a heavy pedestal, or a cumbersome C-clamp. The travel board is also much more stable then any pedestal I've used. The vise can be completely removed from the board in only slightly more time then a c-clamp consumes. While this is not a stream-side vise, it is far from what a few have described.
The Nor-vise is not perfect, it is not for everyone, it is neither the best fit, and finish, nor the worse. Norlander stands behind his products as well as any, and better then some. I know of nothing that can be done on another vise that you cannot do on the Nor-vise, though a few techniques would be extremely difficult on other vises. I do agree the design could be improved, and should be. Am I trying to talk someone into buying one? Absolutely not, I would really suggest trying it before investing.
I would really like to hear specific details to support the negative comments.