It's primarily an art school, with the resources of a film school. Some moderately up-to-date equipment, a lot of super rare analog equipment you won't have a chance to work with elsewhere.
Some faculty positions are constantly in flux, such as the Cinematography position, they can't seem to get it right. The sound department seems very robust, everyone in there is highly skilled. The animators are amazing, take some of their classes (Experimental Animation, not Character)
Have an idea of what kind of filmmaker you want to be and write it down somewhere before attending - there's a ton of amazing work being made or attempted here, but some find they're caught in a popularity contest instead of staying true to themselves. There's the potential to mold any experience you want out of CalArts, truly, but it will take self-initiative. Particularly if you want to be making narrative films - and if so, befriend the MFA Film Directing students, they are narrative focused.