Depends on where your mud holes are. They add weight so depending on te type of mudding you do, weight may or may not matter. If your mud holes take you over rocks and logs and stumps and such, then personally I would not go offroad without them. Here are a few pics of my mudding adventures - and I have rocker rails

 

Fill the holes with the bolts you removed (use a thread treatment on the so they do not rust inside the frame).

If you go OffRoad where there may be obsticles that can come in contact with the body below the doors (rocks, trees, stumps, hard packed sand/dirt, mud with unknown items in them, etc) get some rocker guards!

300-600 can save you thousands in repairs!

 

At Rausch Creek this past weekend, one of the guys hit his and bent it back pretty good (and we were on green trails). They came off later that day in the parking lot lol.