Best thing ever!
Keep in mind that you probably would have been sore without the foam rolling, though 45 minutes of doing anything is a long time.
I roll out my butt and thighs after nearly every workout now, and sometimes at night. As I get older, running and workouts have been making me sorer - the roller really helps. (my glutes and piriformis, in particular, get very sore, but sometimes I turn over and do my quads and IT bands too.)
I can't afford massages anymore, so the roller is the next best thing. If you have calf soreness, google "the stick", which is better for calves than the roller.