Most of the complaints have been that it's TOO fast, and too jerky.
I think I would rather wait for the new firmware.I installed a Phantom 2 yaw switch mod which gave me the option of normal yaw speed and slow yaw speed. The kit consisted of several resisters and a toggle switch, it worked to slow down the yaw speed very well. Don't see why this approach wouldn't work on the x-star. Here's the construction video - DJI Phantom 2 Vision+ Yaw Switch Mod -. Whacking this out for the x-star is above my pay grade. Somebody out there want to make a bunch of x-star pilots happy, have at it.
Here is an updated DJI Phantom 2 Yaw Switch Mod video -. This works on both the Phantom 2 and the Phantom 2 Vision controllers (they/re the same) and hopefully on the X-Star Premium controller.