That one for $6k is either a scam or a steal. 90% chance it's a scam. The Pinside estimate is probably at least closer to the real value. Prices have gone up considerably in the past couple years, so they might not be too far off. Sounds like the pro is probably the better choice if those ads are legit (almost 1/2 the price of the premium?! )...
Best advice is to make sure the seller is legit if buying from an online store. There's lots of threads here discussing the good sellers and the scammers.