I would not recommend you buy one so much as an investment. It is really more important which you like the best especially if you will have it for so long. All those machines are considered classics IMO. I think you may be able to get a TOTAN and WH20 for less than most others on the list and those are very fun pins with a good chance of an increase in price in the future. However, I would not advise getting a pin strictly as an investment.