Tire options: foam, slime, or neither

I'm in the market for a used skid steer and am trying to learn as much as possible before taking the dive. I will be using it to push brush and remove cedar bushes at my place in the Texas hill country with a mix of rocky soil, uneven terrain but nothing too steep. Also there is quite a bit of mesquite which is of concern.

A CAT rep I talked to said for sure to get tires filled with foam. Another independent dealer said not to do that because it adds a lot of weight which will add to...

Tire options: foam, slime, or neither