I have seen them, but not bought and used them.
I have seen an EOTech that got blown out of a humvee in the sandbox and it and the rifle it was on flew many yards before hitting and even denting the hood, but the thing still worked and was zeroed. I have not seen the same from Bushnell. That is my thinking, if you get my drift.
The eotech and the Bushnell are the same item, made by the same manufacturer wiht the same technology. The EOTECH is made to milspec and has a 'hood' over the lens, and is ruggedized.For casual use the Bushnell is a better value. If I were a soldier in the sandbox, I'd definitely want the EOTECH, but for just plinking and range shooting, the Bushnell is fine. The mall ninja crowd will hoot and holler that "it's not a REAL EOTECH" but if they are not paying for it then they can pound sand. Just my 2 cents.
The Holosight was commercially available long before the EOTec. Many IPSC shooters used them with great success. The Holo's are good sights.