If you can find a demo that's got the spec and options you're looking for, then go for it. I had spec'd a list of 10 options, half of which were must haves and half were nice-to-have, so I stuck with my order for a brand new one as I couldn't find a demo/2nd hand one that had all my must-have options that was within my budget.
For the price you're going to be paying just make sure you don't feel like you're having to compromise on the spec otherwise you will not be happy with what you end up with.