I haven't read through the last pages of posts, but there has been some talking about wether this will affect the secondary market. Coming from Europe, I can tell you it WILL affect the secondary market.
Instead of thinking in price and tax I.e. 5000$ + 500$, people will instead consider that they spent 5500$ total price, and when they move to sell they will then base their asking price on those 5500$ and not the 5000$.
It might also drive up the price of the older pinball machines, as the newer ones increase in price, the demand might shift towards older versions thus eventually driving up the price.
This is based on my experience in Denmark, seeing that we pay 25% VAT, I have a good idea what that does to the price - Also in the secondhand market.