I'm a big fan of Sierra Nevada beers, especially the ones on tap at their pub here in town. However, I don't think they really qualify as a "micro" brewery per se. At this point, they've become so big they are just shy of a macro brewery...especially since last year they added even more production.
But last year I went to a little place up in McKinleyville, CA called Six Rivers Brewery
. Nice little pub overlooking the coast, and inexpensive but good food. But the best part about that place was their Kona Moon Porter. I had to take a big growler to go it was so good. Their other beers were also very good, including a Chili Pepper Ale I fully expected to dislike. I think what I like about them is that their brewing area is just off the main tap room, and they brew it up in pretty small batches. I think these small batches keep the flavor of the beers variable, and I appreciate the variety.
I used to like it more when Sierra Nevada was smaller, and their Pale Ale would taste just a bit different for each batch they made. Their seasonals are still different year to year, but I miss the smaller brewery. That being said, I'm very impressed with SNs consistency and their commitment to responsible brewing. They've done a lot for the community here and are incredibly environmentally friendly. Last year they brought in hydrogen fuel cell generators and a huge array of solar panels to power the whole brewery. It's pretty cool that even as a large company, they are willing to sacrifice some profit for the good of the environment.