I've used Zona razor saws. It might lessen their life(I've dulled at least one), but they can handle it.
I don't have a teeth per inch spec handy for the ones I had used, but I can take a ruler to one later (assuming I can find the one that I didn't dull down too much 
)to get a guestimate for you.
I've done it without a vice as well, just holding the track down to a rigid table or maybe a block of wood (2x4, etc) with my other hand. I figure I risk deforming the track more by clamping it in a vice than I gain.
It is necessary to use a small file to smooth out the rough edge after the cut, but nothing too involved. A couple strokes with any needle file on each rail, as well as some where the track pins will go is normally enough.
Edit: looks like the one I used was 32 teeth per inch.
-Dave
