I like it a lot even though almost all of my functions have no dispatch (only one implementation) or single dispatch (implementation differs based on the type of just one of the arguments).

Firstly I like the aesthetic and implications of f(x, y, z) over x.f(y, z). I like that f is its own thing and not a property of x.

Secondly, it's really nice to be able to reach however far down the callstack you need to go to patch some function "owned" by someone else to act correctly or more efficiently with whatever your type is. You can get correct code most of the time with single dispatch and well-thought-out interfaces, but getting interfaces right in advance is really tricky and requires coordination with other users of the interface whereas multiple dispatch can often work well without much coordination and can also handle cases where you want the implementation to vary dramatically based on the type (the OneHotVector in Karpinski's "Unreasonable effectiveness of multiple dispatch" talk is an example of this).