I made a new top for my front rest out of UMHW plastic and turned it into a barrel sled base. After seeing the results, my dad has decided to give one a shot, but decided to get a sled from Vanwey rather than the plastic one I made, but now that he has it, it raised a question for me. 

On the sled I made, I made the base 1.5" wide, which is the max rules allow. My thoughts were that the wide, flat base, will help keep the rifle from rolling during recoil and help the rifle come straight back.
On Vanwey's sled, the base has wheels, and if you take them off, the bottom is rounded. I understand that will minimize surface contact and perhaps allow the rifle to slide back easier, but would that cause the rifle to rock back under recoil so you end up looking at the sky more?

Curious about others thoughts and any experience with both. One I build the base for his, I will definitely try a group on both rests to see what happens.

I've been using one of Jerry's front sleds for years.  It never leaves the surface of the plate on my rest and, if I hold the gun the same way each time, winds up pointed in the same direction at the end of the recoil.  (Which is helpful in reminding me when I'm not paying sufficient attention.)

Just love my brass/aluminum sled from  Jerry?. I'll take a pic of the quick change plate I made to fit my Randolph Rest. Really the way to go to wring out A barrel,then shoot it off the forearm and barrel to test also.
A buddy made a delrin rest like yours and it works for him !
The leather under the wheels helps alot......