hi mesaboogie
if you can afford a rototrim that is a good brand
or something "like it" ( rotary cutter ). they work well AND are pricey
you can also look into getting a simple guillotine cutter.
i've 2 of them they aren't too expensive ( i think mine are 12x12? ).
they work well unless you are cutting a stack of things, or something very thick.
stacks of things will creep and be an uneven cut, unless you are good at
putting pressure on the top sheets to keep everything in 1 place
adn cutting thick things ( like single ply mat board and cardboard &c ) works
only as well as you are good at holding it and cutting. some swing arms aren't too sharp
so it frays while it cuts something thick.
if you find a swing arm ( guillotine ) cutter and it has a 2nd arm that comes down,
that is what is used to pressure the paper \/ board so it doesn't move, used by bookbinders and printshops
really kind of expensive but who knows maybe craigs list sal's place, good will or a use office supply place&c
are your friend. old cutters may be inexpensive, sturdy and if you bring them to a sharpening place they can
make them work like they were brand new.
good luck !
john