I have been riding my spatulas every day since i got them, wether its powder, corn snow, or ice, (and I also have hellbents and chopsticks) so they can be ridden in any condition and you can carve them but it is entirely different than a normal ski and you have to figure it out, and if there is a little fresh snow on the groomers then they ski perfectly fine.
I would assume that the ARG would ride fairly better on groomers and hardpack, and also a lot of times a bad tune can make a reverse sidecuted ski ride poorly on groomers.
Finally, reverse sidecuted skis shred powder so much better than something that is just rockered, when I first rode the Spatulas I realized that the bents and chopsticks actually don't slarve very well in powder at all.