I've noticed the difference, but never commented on it. The testing islands have always had jacked up rates compared to Atamara. The spawns on Atamara are so weak they're a joke for the most part, nothing more than an irritating but necessary means for knights in realms at peace to gain some honor and prestige.
I'd actually most like to see the rates adjusted on the stable islands, myself (particularly Atamara), but if we need a guinea pig Beluaterra is always a good option.
