Oh wow, where to begin.  I used these out on our front porch about five years ago for hanging Christmas lights and they are still going strong.  I keep the lights up year round and I thought by now the sun and cold weather we get would have cracked them but no.  I have had to replace a backing strip a few times but with our extreme weather that is just fine with me.  I love that you can't even see them and they last a very long time.