I have an old EoTech 557, no longer made. When it failed about year after purchase, EoTech upgraded the battery contacts on warranty, been fine ever since. I use EoTech 3x G33 quick release magnifier behind it.
The Eotech co-witnesses the front post and Troy BUIS, so I can shoot irons through the Eotech, or remove it with a coin. It holds zero quite well after I remove it and reattach it.
The EoTech would be the go-to for a fight, but I usually shoot the irons just because I enjoy it.