I cable tied my RGB light strip to the conduit (after the conduit was put into it's correct shape, with some reo bars nailed into the ground). These replaced my LED arches I had last year, which I sold to another member.
I did think about using a PVC pipe and then heating it so it would keep the shape and then drilling holes through it for the larger LED lights.
The only thing is, I havent had much success at bending the PVC piping, even with filling the thing with hot sand, it still lost its shape, and if it isnt molded, then the pipe would collapse where the holes are drilled.
Please bear with me guys I am a total newbie. I also saw the video and thought it a good idea. After a bit of research and a few visits to garden centres, I came up with Link edge. The product is very similar to the plastic one in the video but made from aluminium. A 3m long section is $35. The website is www.linkedge.com.au and it has a search facility to find your local supplier. Slightly pricey but could be useful.
I know this is an old thread but were any of you folks able to get that edging? I manged to to two 20ft rolls over here in Alberta, Canada for $8.50 a roll. The fellow made another video after that that 1ft one where he had to strengthen his arches. https://www.youtube.com/watch?v=PHv-m9kW2V8&feature=player_detailpage