There really isn't a downside that I can think of, but I don't believe it is actually a "showroom" model because that model has changed since 2006 - so it would not be representative of a new one.
It is more likely old stock that has been sitting around, although I cannot imagine why a dealer would have it.
Make sure it isn't a rebuild
or taken on trade
or returned because of warranty issues or any other reason for it not to be new stock that was forgotten in a corner by mistake.
I would expect a whopping deal on it. I would consider it "used and in good shape" when it came to pricing.
Get a carb rebuild
kit, plugs and an impeller at the same time and you won't need to worry about parts