Ours does because, well, why not? On one side we didn't have any, for ramp purposes. (Although I think it wouldn't have changed it much, it seems like it'd be sort of hard for a couple of pool noodles covered in smooth cloth to keep a high power, high traction, 6 wheel drive with good ground clearance off the ramp.) The other sides had them, except a small opening for ball collection. And, believe you me, we'd have been in sorry shape after the elims without them. However, Sparky didn't have them, and from what I saw, their frame still seemed to be in fine shape at the end of VCU. (I could be wrong, it's not like I examined it) As for them reducing defensive ability, If you were at VCU and watched us play, you might have noticed that we played almost entirely defense (yet at the beginning of Saturday we had the 4th highest avg match score, go figure
) we never felt that they were hurting us. Collision physics aside, that 15 lbs (Ours were about 10) gives you a good bit more traction, and in a pushing match against a similar drivetrain, this'll make the difference, not how hard your (illegal) high speed ramming is.