I think the general consensus is that corrugated soles were a marketing gimmick and have no effect on plane performance. (Though it may aid in lapping the sole quicker if that's necessary, but hope upon hopes that it's not.) I have a corrugated #3 and #7, and normal #4 and #5. There's no difference in my experience. That ebay plane is a knockoff, not a Stanley or a Sargent, so it's really not possible to say how good or bad it might be. For 99 cents though you sure could roll the dice! If nothing else, basically any #5 plane can bake an OK fore plane for rough dimensioning of wood. I would lean toward getting an old Stanley, but I must say I'm surprised by how good the Grizzly reviews are.