I am very happy with PDF XChange viewer on windows, since it renders very quick and efficiently, while having many features for annotation/marking/etc that is u

I am very happy with PDF XChange viewer on windows, since it renders very quick and efficiently, while having many features for annotation/marking/etc that is usually not available. Eg highlighting text, text boxes, arrows, polygons, etc. Very fast to zoom, scroll, pan. Since I am a tab hoarder, naturally my PDFX has a couple of pdf tabs too, so it takes a little while to open - so if I want to just quickly view a file, I drag and drop it onto firefox.