Well, shit. I already got solid oak and built my blocks. Thanks for the plastic block reference, I intend to check it out before I install anything, though. Trying to get a picture uploaded for you. My waters are very shallow, so my blocks get a lot more force pushing through the shallows in late summer. At least, more of a beating than the kit's blocks were intended to take. You can see the two original blocks laying on the side-deck. I've split them multiple times.