Pressing seams open does take a long time; it can be maddening. I pressed all my seams to the side when I first began quilting because I'd read it was the right thing to do. Then "pressing seams open" came along. I admit, that as a long time garment sewer, I'm inclined to press seams open; it somehow just feels right. But I also admit that in quilt making I mix it up -- sometimes I press to the side, sometimes open. Depends on the block....and my mood and patience, I expect!