I built out a franken-rail using multiple vendor products and used Design Rail for the hand rails over Trex post sleeves. I built a hole template on a piece of cardboard using the instructions provided and it worked great. These aluminum rails are easy to cut cleanly without marring/chipping using a combination blade on my miter saw. Originally I was using blue painters tape to try and protect the surface, but eventually stopped doing that as the cuts were all clean and saved time. I used a laser measure to identify exact length to cut and fit very cleanly. I recommend starting with the longest rail sections first in case you mis-measure and can use that section for a smaller area to avoid any waste. The rails all arrived well packaged/protected and had zero defects so would definitely recommend these to friends or if I am doing another project where railing is required.