I have an EOTech/Aimpoint magnifier on mine that has never failed or had problems in 9 years. EOTech is good in my opinion but I’d recommend any Aimpoint but those end up being pricey. You’re paying for the durability, Aimpoint is arguably the strongest/best red dot optics out there. I’d you want to go a cheaper route that gives you quality and a lifetime warranty, check out Vortex. I have a Vortex Sparc on an AR-9 build and I absolutely love it. Zero’ed it once 3 years ago and haven’t had to since. I have a Vortex Viper red dot on a Glock 19 and a Vortex Viper PST Gen II (3-15x) on a 30-06. Never had any problems with any Vortex optic. Quality is amazing and price point is cheap. I love SIG but I’ve never owned a SIG optic and I haven’t heard the greatest reviews about them. Definitely do research and compare a buncha red dots. You can really deep dive optics purchases by making a list of what features you want/need and make a list of potential optics that work for your wants/needs. I’m sure others will weigh in with their personal recommendations too. I can only personally speak to EOTech, Aimpoint and Vortex unfortunately.