It sucks. I spent $10 for the "system" which had nothing more then a syringe, pin, alcohol swab, and a plastic suction thing.
Direction said to leave it with tube upside down for 30 min in direct sunlight and 1 hour on cloudy days. I left it on for about 1 hour even though it was sunny. When I took it off, the epoxy still didn't dry so it spilled down my window. I was like wtf, it was in direct sunlight and its 80 degrees outside!
I'll rather wait till it cracks more and then replace windshield.