I actually used the PVC clamps and they worked out really well. I used them to install both the rails and the deck. I used varying sizes of pipe depending upon how far I needed to open the clamp. It was a simple and cheap alternative to spring clamps or C clamps. I did have to use some good C clamps for the rail, but did not need too many. When I installed the deck I also loaded up the deck with anything heavy that I could find. It looks pretty funny, but it worked. Here are some photos: