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.
Even eminent chartered accountants are known, in their capacity as fishermen, blissfully to ignore differences between seven and ten inches, half a pound and two pounds, three fish and a dozen fish. ~ William Sherwood Fox, Silken Lines and Silver Hooks, 1954