On my journey on a switch from OS X to Windows 10 one of the missing bits in the daily usage was the „Quick Look“ / Preview feature in OS X. Its annoying having to double click in explorer lists, just to see whats in the file.
Throwing in seer, which does exactly that – its customizable with shortcuts and extendable via plugins (autocad, office etc.).
The office plugin isn’t the best to be honest, the natve picture, pdf etc. previes are working as expected: fast and stable.