cutting colourbond fencing panels

I need to trim the top of a colorbond fence that is about 30 meters long and I'm wondering what the best method for cutting this would be. The profile has the deep triangle sections so it is impossible to use any type of tin snips etc. Nibbler would take too long. Angle grinder tends to burn the finish and leave a burr. I'm considering buying a rotary hacksaw type blade for my circular saw but I would like to get some feedback on how good these blades cut this type of fence/roof sheeting as the blades are not cheap and want to be sure before I go out and buy one. I was also wondering about those twin cutting blade saws that you can pick up at Bunnings cheaply. In the past I have borrowed a blade from a circular saw that was about 50 years old. It had square teeth but was not carbide tipped, just tool steel I assume. It worked ok but left a nasty burr that had to be filed off afterwards.