Voidu.com - legit?

It's legit, I've been using it for quite some time now.

Owners are complete morons though.

Also, be aware most keys have region locks and they never inform you about it before.

Why when you can go to other known trusted sites ?

Also , Merry Christmas !

Never heard of them. Checked out their store now and they didn't have most of the games I'm interested in, and those they do have are significantly more expensive than on steam lol.

They're verified on /r/gamedeals and ITAD, can't get much more legit than that.

The Dubai address despite being registered in Netherlands in itself is not a cause of alarm, it is standard with international stores. GOG itself was used to be registered in Cyprus, despite maintaining all of the offices in Poland (they officially moved from the tax haven back home this year).
They seem to be legit, although not exactly professionals.

Call of Duty® 4: Modern Warfare® (Mac/Pc)
Call of Duty®: Modern Warfare® 2 (Mac/Pc)

Is it possible to play these versions from Voidu on Windows?