Traction (ability to stay on platform) - Omni vs Traditional

I didn’t include Mecanum wheels as I knew that they wouldn’t be a good choice, but in terms of staying on platforms (which is an important part of this years competition), which wheels do you guys feel have the edge? Omnis or Traditionals?

Omni wheels have the higher traction than the standard 4" “traction” wheel (in the direction of wheel travel – obviously the omnis have much less traction if you pull the robot to the side)

See this page:

and this thread:

for more info.

(yes, it is funny that “traction wheels” are not the highest-traction wheels available)