I have very bad arthritis in my leg and always rent an ECV at all the theme parks. I've been to AK twice and I don't remember having any problems. I do know that sometimes the ECV you rent just doesn't go very fast, I don't know if that's because it's not charged right or what but it is a little slow then especially going uphill. The only time I ever had a problem was at Universal. We got caught in the rain, which happens every day in August there, but this time something shorted out in my ECV. We were leaving the park and all of a sudden my ECV started going really fast and there were people in my way! I took my hands off the handles but it still kept going! So I put it in reverse but it just started going backwards on it's own. I finally thought to pull the key out and it stopped. They came and picked it up and brought me another one but did it ever scare me