I would never buy a model that I haven't walked through, and here is why.
I looked at a LOT of trailer floor plans when I was doing research for my current trailer. I liked the floor plans on several models... but when I actually walked through trailers, sometimes the floor plan that looked so good on a computer screen turned out to be wasted or uncomfortable space in person.
Northwoods RV's are a little more expensive than regular trailers. I would invest a 12 hour drive and a night in a hotel to see the floor plan in person before buying it. It stinks now... but its a LOT cheaper and less aggravating to test and be certain BEFORE you drop $40K on it.
Now, if you have already walked through one and know you like it, that is a different story. Technically I bought mine sight unseen, because I ordered it and showed up on delivery day to pick it up. I made sure that everything was to my specifications and right before we accepted delivery though.