I have a Love-Despair thing with Prog Rock. I absolutely love it. It also drives me crazy(ier) when it loses its musicality in favor of a technical exercise. I enjoy the technical brilliance and complexity, but sometimes, it seems many bands sacrifice a good melody or the "feel" for blinding wizardry.
Watching a band play things so complex it causes brain damage is fun, but it leaves me cold when it devolves into noise. I enjoy it when a band uses their technical expertise to enhance the song, rather than obliterate it. For me, the song is what really matters. Sometimes, I miss that in Prog Rock.