James- prices have already climbed. You lucked out- and I got my QL-50 (arm swappable version of yours) just before the prices went up.
It's inevitable- they with crest, and prices will crash.
Yes, they will, just as prices on Garrard 301s and 401s and Thorens TD124s have crashed...
Actually, the price will crash if there is a "fever bubble", a speculative rash of buying that drives the price up temporarily above the long-term equilibrium point of supply and demand, by temporarily pushing demand up too much. For example, if a whole slew of people read this thread and decide they MUST have a JVC TT, then they may bid the Fleabay prices up to unsustainable prices in the short-medium term, and prices will fall back as (1) some decide they don't need one after all, and (2) more of them are offered for sale, since they are bringing higher prices. The "fly in the ointment" for this scenario may be the actual quality of the TTs, and whether people are willing to release them at the higher prices, as well as how many there actually are out there to be released onto the market. If people love them so much that once they buy one, they won't re-sell them, and the total number available is limited (and below the sustained demand), then the supply will be diminishing at the same time that demand is not, and prices will continue to rise, perhaps to be sustained at a new, higher level (as with 301s).
But most likely you are right; prices of audio gear that "gets attention" in the market tend to fluctuate according to the bubble-and-burst pattern you describe. I saw that happen locally with Marantz receivers and Dual turntables. Their prices went high (above Fleabay levels) for a while, but have have fallen back to lower levels in the past couple of years, as the dominant (Mainland Chinese) buyers in the market have moved on to other things they have learned about. Nakamichi cassette decks became "hot" after those, and haven't burst yet, as far as I know. I'm not sure what the latest bubble to form is.
