Well it took me like 3 hours 15 minutes the other day from start to finish, and I was so rusty, I died at least 80 times, I'd say. I can easily beat it in probably half the time if I'm more careful.
I'm currently playing this game on my YouTube channel, I'll post the total time for completion once I finish recording. It's going on YouTube unedited, just in multiple recordings. --- Check out my YouTube gaming channel! http://www.youtube.com/Decon082/