In case you have not laid your money down on the Bushnell, I like the C-More railway reflex 6MOA red dot ($300) in cowitness with a fixed front sight tower and folding rear sight. It is rugged, low profile, parallax free, reliable, high quality, and moderately priced. I works well with both eyes wide open. It has impressed everyone who has tried it. They make a raised version specific for the AR flattop rail, but I found the regular version puts the dot just where I want it (in cowitness with my irons). It does not have a lens cover, but I found one made for another brand NcSTAR that fits perfectly. It does not have click adjustments for the windage and elevation which would make sighting-in trial and error if you don't use irons or a laser bore sighter. For cowitness it is easy. Adjust your irons for point of impact and then dial the red dot so it is perched on the tip of the front sight.
So you own this Bushnell Holosight? How do you like it? What are its features? I am not familiar with it.