I, (hubby and I actually), used to make our own masonite boards but I just want to get to the painting. Took too much time. I know, I could get a lot of them done with only one day devoted to this but I am not interested either. I hate to sand. I'm a perfectionist and it's hard to get them absolutely without blemish. Hubby is busy. And you can find them with really good prices now. So I buy them.
Of course, I did have to send a whole bunch of cradled wood panel boards back to DickBlick that weren't perfect. I mean, obviously not square 5x5s, 6x6s, 4x4s. So, I guess it's not that easy.