From various competitions we have not been ruled illegal by using some non-vex flex tubes for holding wires together. Are they illegal or not? ???
VEX Robotics Competition Nothing But Net Game Manual <R7l> Commercially available items used solely for the purpose of bundling or wrapping of 2-wire, 3-wire, 4-wire cables, and pneumatic tubing, for the purposes of protection, organization, or management are allowed. This includes but is not limited to electrical tape, cable carrier, cable track, etc. Note: it is up to inspectors to determine whether a component is serving a function beyond protecting and managing cables.
Copy pasted from the thread where Karthik answered your question on 3-D printed wire holders. According to this rule, as long as you’re only using those tubes for organizing your wires, you should be in the clear.
Commercially available cable management products are perfectly legal. We use them all the time. Usually just the cheap “wire loom” plastic stuff.
RoboSource.net has some very cheap wire-loom options! They are competition legal as well.
McMaster Carr has some nice options too. I’m not a fan of the plastic wire loom.