I had the Deep Impact many many moons ago - personally i found it to be a pile of poo, and sold it. Its no more worth £600/700 than a 60's Fender J bass is worth £XXXXXX
Its just the fever kids start when some face starts using a pedal, and they all drive the price up to disproportionate levels, way above sensible. The price, now, is what fascinates the unwary + the lack of them for sale, thinking this must be the dogs nuts. It isnt
The only reason i'd buy one now was if i saw one for sale for peanuts and would simply sell it on to a mug with too much money, so i could buy something useful