The thing that will weigh over you at both schools is that your desired path is not guaranteed at either.
Maintaining a 3.2 in engineering is not as easy as it may sound and intangibles like sickness, depression, and lack of focus can easily derail that. The competition will be much more fierce. I’m not in any way saying you can’t do it. The engineering curriculum is hard everywhere. So, there’s some risk at MN.
Changing majors at Poly is absolutely not as easy as simply having a 2.0. There are lots of hoops you have to jump through and the curriculum for admission varies from department to department. Some of it is your pre-admission statistics which involve more than just GPA and test scores. It’s also based on availability within the major you want. With that said, switching probably isn’t as hard as it is made out to be. Again, not guaranteed.
So, it really gets down to what program you like better.
As @cadave has said, they both have good reputations, but are very different.
First Minnesota. On weather alone, MN will be drastically colder than anything you’ve ever experienced in your life. It’s in a good city with lots of city things to do (restaurants, concerts, clubs, etc), but that comes with more traffic, congestion, etc. It has a big time athletic program with tailgating, etc. The class sizes will be much larger at MN with many/most of the labs and discussions taught by graduate assistants. The engineering curriculum doesn’t really start until second year, much like UDub.
SLO is very isolated. Most love that because it’s like being in say Santa Barbara 50 years ago. It isn’t overrun with people, pollution, etc. For a few though, it can feel small. The ones who usually voice this are typically from Orange County. It’s all relative. For me personally, it’s one of the most idyllic places in CA. The weather is always nice, 70s and sunny is the typical report back to us. Class sizes are small to medium all taught by professors including the labs. You start “getting your hands dirty” as a freshman. It’s on the quarter system. You don’t really give up any theory in exchange for the “hands on.” It’s very rigorous, not known for grade inflation. All in all very undergraduate oriented with engineering the jewel in its crown.
With both there will be administrative hassles. You get that with almost all schools now days, but especially state schools. Scheduling classes is an art that is best learned early on. The campus food won’t be great at either. Again, state school. Job placement will be good at both as long as you keep your grades up. A 3.8 from Podunk U has an edge over a 2.2 from MIT in most job searches. You will see more regional recruiters at each respective school. Both will get national recruiters, but if you know you want to work in the Midwest, you will have more opportunities fall into your lap an MN than at CP. The same holds true in reverse if you want to come back west. You’ll see more Tesla, Apple and Boeing recruiters at CP than MN.
In the final analysis, they are both good opportunities. Congratulations. You will do fine at either. Good luck!