If you think that a solid state...always on...artificial horizon system is less stable and dependable than a vacuum driven gyro system, or electrically driven gyro system, or mechanical system...we are in different solar systems.

I have flown many artificial horizon systems. The new digital...always on....fully electronic systems are awesome.

Get real. Understand that when you get sucked into the soup that you need accurate information that is instantly understandable, right now.

With the LX Nav S80 system (or Butterfly vario system) you are never more than two button pushes away from an instantly understandable and fully up to speed display that, if you understand it, will save your sorry ass.

Take your alternative systems into a dual aircraft and put some real blinders on and see how you do. You cannot accurately touch virtual buttons on your smartphones while tumbling inside a cloud. You cannot wait for a system to boot from a cold start. Your rational mind will not be working when you try to understand how a compass, ASI, and bubble need to be responded to when you have not practiced this over and over and over.