I thought I would pass on what I've learned from making this boat watertight. First, both gluv-it and steelflex are really nice products. There was plenty of information on steelflex on any number on threads, not much on gluv-it. Gluv-it does cost more, but has much, much, better coverage than steelflex. Gluv-it is also available in both quarts and gallons, as is steelflex. Which one you use really depends on whether you want to paint the outside of the boat, or the inside. Gluv-it is easy to paint, and has a longer working live before it starts to set up. Steelflex is difficult to apply due to how thick it is and sets fast. Gluv-it really works it's way into crevices and flows well, no drips. Can't say that about steelflex at all, though it does stick to everything extremely well once set up. I wouldn't want anything else on the bottom of my boat. The worst thing about steelflex is having to order through the manufacturer who doesn't do web sales or even take a card over the phone. Gluv-it you can buy from any number of suppliers.