Got a lot of good opinions here. I actually love leg day, today was leg day and I love the feeling after when it feels like my legs can't support me.
The only reason I asked is because when I was younger I didn't work out legs at the gym and I didn't ride bikes yet. When I started riding fixed I noticed fast and great improvements in my leg muscles. I was able to see my calves for the first time and my quads became beasts. So, I thought cycling was a total leg workout. Guess I will still go to the gym for legs. Cycling can be more of a cardio for my with the added benefit to legs.