Spotchecker,I got my 320 4 or5yrs ago and like it very much. For the price, the unit can do alot. If I remember right,you can for free download a program so you can see what the unit does.If I remember right the 480 is just a little more coin but,you can put a chip,like Lakemaster in it and your all set to go.Back to the 320,I'm very happy with it and would go out on a limb and say it is well worth your time and money.
If you've got short, stubby fingers and wear reading glasses, any relaxation you would normally derive from fly fishing is completely eliminated when you try to tie on a fly. ~ Jack Ohman, Fear of Fly Fishing, 1988