I am a little confused on the math. 30 miles in 1 hour 15 minutes is a 24mph average and that seems pretty high for a mountain bike. No matter what the speed 30 miles is great. Good Job.

One thing I have learned (especially since I am just getting back into cycling again) is that what other people think, and how fast they go doesn't matter. At this point as long as you are riding farther and faster than you did before then you are making progress and that is all any of us can ask for. I am always thrilled when I look down and I have gone farther in an hour than I did last week or When my time on my commute is faster than before. I ride for me and no one else!