Actually the free version of CorrectReference will automatically find assign the .jpg bump files if it can't find the .bum's in most cases....but not all :) I use P5 and frankly P5 does not use the .bum files properly anyway. The .jpg versions can be connected to the .bump node and tweaked to give good enough results for on-screen work. I had 425 mb of .bum files in my texture folder!! Converting to "best quality" .jpg put that at about 65 mb. Comparing the two visually in Psp, I could see no difference. $20 seems reasonable to me :)