ARKit object placement drifting?

I'm wondering if anybody is seeing truly solid world placement of your object with ARKit? I constantly see drift happening even with the default samples that ship with the ARKit unity plugin.
Tried it under many different light configuration and different environments, but nothing shows any real improvements.
The models that I'm displaying are pretty small ( 14 inches or so in width), but then again, the default ARKit samples are also pretty small, and I'd have thought that the samples would display correct tracking behavior.
Any workaround?

 

Has nothing to do with Unity or the code in your project, and because it is apple's code that does the tracking.
Make sure you are in a bright environment with no movement visible to the camera. Also don't be in a moving object yourself (bus/train).
And make sure your environment has enough "features". A wooden floor is great. A supersmooth white reflective floor is not good.
I did experience a some differences between iOS devices in tracking. Seems like some are a bit better calibrated than others? Not sure though.

 

are you anchoring? are you hit testing in a way that only finds actual surfaces? are you resetting world origin? these can all help.

What about scale of world and assets? that can affect drift too.