I use it all the time. Mainly for just recording the orders and printing invoices as not all the functionality is relevant to me.
You do have to get used to it and spend some time understanding it as some of it is confusing to us in the UK but it's better than some of the others out there.
The only thing it doesn't do which is key for me and perhaps others over here, is match up items within offers but in software it's hard to keep everyone happy I guess

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It's well worth at least having a look at the demo and see what you think (unless you already are using it of course).