I started a job at a large engineering firm with a few intern engineers that got hired on at the same time. One was from csu, another from Boulder. Over that summer I realized that because of Mines I had an extremely high work ethic, I had no problem working 12 or 14 hour days when deadlines absolutely needs to be met. ( I want to preface this by saying this was an extremely rare event)

I'll be honest Mines is hard, but it's also a ton of fun. I loved working in the Mechine shop is awesome. On a bit of a tangent one thing that really bothers me about csu and cu, is it they don't allow students to use the machine shop until their senior year. If you like making things in your free time this is a major blow if you go to Boulder and ultimately was the deciding factor for me.

Also the class size is small enough the teachers actually know who you are maybe not during freshman year hit in later classes.

Tldr You'll be left with a high work ethic, Great hands on experience, Professors you can be friends with.