Linear rails vs open v-track wheel

Hello;

Please excuse what may be a very newbie question. And I apologize if I have butchered the technical names. I am new to Open V- track. And also sorry if these questions are answered in the video (of the Ox). I had to skim it.

I am early in the planning stages of designing my own CNC router. I intent to use it for hobby style woodworking and maybe some small aluminum parts with a 2ft x3ft working area. I was surprised to see show many designs use open- v-track rubber wheels on this...

Linear rails vs open v-track wheel