What do you guys think of the S-Works Power saddle?

I'm curious because it came with my used bike (back when I was completely new to cycling) so I just rode it from day one. It feels comfortable (other than my butt starting to go a little numb after the 2.5 hour mark) - but again I've never ridden anything else so I don't really know what "comfortable" should feel like.

There seems to be a good amount of experienced fitters in this thread - would love to get your thoughts and opinions on this saddle.