They are quality yoyos for their vintage. My estimate is that ebay prices are inflated. I know some ebay people think something is worth way more that it acrually is. It would be interetsing to see the actual sale price on them.
I’ve recently sold some YYJ Hitman yoyos for $20-$35 depending on condition. They tend to develop stress fractures in the plastic. I’ve had a couple of pristine, rarely played ones that I let go for cheap because they cracked.
Here’s some recent examples of hyped prices on ebay: