Does this sealed KQV seem legit to you? The main difference with the other editions I own is that it doesn't have "golden" letters, and does have a design on the top and bottom of the box (unlike ALL editions I've seen of the Big Box KQ5 on the internet). It also weighs way less than the other 2 editions I own.

Are you sure it isn't just a variant box?

And I thought I owned them all lol

It kinda looks legit, but also really low budget and bad. Too cheap to include manuals? Wow, just wow.

There were tons of discount boxed PC game Companies in the 90s that would distribute older games for a discount, so I wouldn't be surprised. It could easily have come from Circuit City or CompUSA, that kind of place, but very late in the game. Probably the best place to ask is Vogons forum, there are a bunch of Sierra nuts there that could probably tell you whether or not Sierra was doing that themselves, or was possibly licensing the older titles out to discount software distros.