I don't have experience with WOW on any of their KSs but I do back when he was selling already printed kits.
In a nutshell, that experience was very bad. I placed two orders. In the first case I was told the kits were in stock and shipping. My $200 USD order never shipped and after payment I never heard another word from WOW. I ended up filing a PayPal complaint to get my money back.
A year or two later I thought I'd give him another try. I did get a few emails with lots of promises to deliver, then lots of excuses, and finally a lie telling me the order shipped. After I asked for the tracking info I never heard a peep and went through the PayPal refund process again.
As for his KSs, I do know that the sci-fi one he did was a bit muddled. After looking through the comments I saw a lot of the same excuses.
I don't do 3D printing but a consistent comment an all of the KSs seems to be errors in the files. Maybe I'm wrong but to me, that says some designs are never test printed or maybe have limited printing to see the actual results.
I'll give him credit that he is ambitious and his drawings all look great on the computer.
Given past multiple experiences with WOW however, they won't be getting any of my money.
The 3D market is exploding with offerings. Somebody else will be along shortly…