POS licenses and versions

[matrophy]

I am thinking of adding POS to our store and I remember someone from Intuit at a trade show (where they'll tell you anything you want to hear as long as you stop by their booth) telling me that I could use one license on 2 machines. Something about one machine being 'master' and one the 'slave'. Is this true and is this a workable solution? I plan on having POS on one machine in the fromt of the store doing POS and sales transactions and one machine in the office for the rest of the financials.

Secondly, I can get a pretty good deal on POS v4 and pay through the nose for v5. Is there that much of a difference between the 2 versions and if so, what would I be missing out on if I decided to buy version 4?

We are a retail store that sells about 1/2 of our items off the shelf and need to keep track of all of the part numbers more easily than we're doing now. We want to add barcode capability and since we're using QB for financials now, want to stay with the QB POS. The other 1/2 of what we sell are assembled to order from parts that are purchased for the order so inventory control is not that important.