Thanks for the reply. Bandit, have you shot either of them in bright sunlight from a lightly shaded area? Such as from under an overhang into an open area, One of our outdoor areas is like this and my dot with the Shield disappears. If I'm standing directly in bright sunlight shooting into an open area it is just bright enough but certainly doesn't draw your eye to itself. And I have seen the "jittering" you describe with this sight.
I have a Sig Romeo Zero coming to try; 6 moa, manual adjustment (hoping I can set it to a compromise setting and leave it), shake awake and claims, I believe, 10,000 hour battery life. And they're on sale everywhere for not much over $150.