I still have plenty of opps paint and primer I have gotten away from using it. Oh, I still use it when I need to sand and finish an old piece of woodware or a nuc that I need ASAP. In these cases I just put on 3 coats of primer.
I have found at Cabot's (Blue label) beats paint hands down. I use the "Natural" stain. No matter what wood the boxes are made from, they all look good. Cedar and cypress really stand out. I will apply 3 to 4 coats of Cabot's.
A year later you cannot tell that the boxes have been in the elements but the painted boxes have already started to show some wear. It doesn't matter whether I used oil based or latex. Neither holds up that well compared to the Cabot's coated boxes.
It costs a lot more for a gallon of Cabots. $30 compared to $5 for a gallon of oops paint (not counting primer). But I "painted" 6 bottom boards with landing boards (Kelly's), 6 brood boxes, 6 ICs, 6 OCs, and 12 medium supers. (All 8-frame equipment.) I still have some left.
An added benefit is that Cabot's will be soaked up on the end pieces until they are saturated and will not split or want to rot.