I ski the R:EX in a 184 and previously skied it in a 191. Let me say that length makes a big difference. The 191 craves speed (on any kind of snow) and favors large radius turns. In fact, short turns were close to impossible. The 184 is quite a different story. For skiing at Squaw and Mammoth, the 184 R:EX is a great single quiver ski. They still take some work in tight places, such as chutes, but are quite manageable. I feel that they are very capable and solid on steeps, as well. The R:EX is really a great all-terrain choice.
That being said, I have skied the Sugar Daddy (173), but never the Gotama. The R:EX has a lot more sidecut than the Sugar Daddy and therefore is more friendly to groomed snow, where they absolutely rip. The Sugars would obviously be better in pow, though. Crud performance would be a toss-up, based on personal preference.