The Rawhide looks like a perfectly fine portable ... for solid or dry ground.  The sales brouchures don't show them set up anywhere it gets muddy.

I've got the Titan West portable and when we catch / sort / load cattle when it's a little wet, the pens and alley don't stay solid and smooth too long. 

Those little wheels on the Rawhide are what kept me from buying one.  I'm pretty certain here in north MO, there's gonna be some soft ground at least half the time, if not more, when I wanna use the thing.  It just doesn't look like much fun trying to roll those little wheels through soft ground that's been tromped all to he!! by several head of cattle for an hour or two. 

The places where we use it--we try and set it up where the trailers can load easily out of it and still make it out of the field, like in the same general area close to the road.  And when we take the corral back to where we've used it before, even if it's dry, the holes / tracks from the previous use are still there.  It's not a problem for swinging the panels when they're suspended by a cable and winch, but I'd hate to try and "roll" those gates/panels out over those same holes / tracks.

my 2 cents