Let me start with this...we are not hikers, in the midwest when someone asks you to hike its usually to the top of the street to get more beer.
Anyway...my wife and I hiked the challio trail and it's a bit deceptive. The first 50% is just pretty easy but then the challenge begins. There is no question you need to be in great shape, not be afraid of heights...but that said its well worth it. We made it to the top, I'm sure we will be sore tomorrow, but was well worth. Net...give it a try, take lots of water and make sure you take your time.