My girlfriend and I did this - our first time each riding ATVs and honestly, we were both pretty scared. After a quick intro and obstacle course, we got into vans and headed to the trail start site (we also had the option to drive ourselves if we wanted to).
Of a larger group of about 15 or so, we were broken up into 3 groups - our group had 5 ATVs and our group leader was Lee. First off I got to say Lee was one of the coolest and funniest dudes - he was extremely helpful in terms of giving information, telling stories, and most importantly, being kind to everybody in our group.
The ATV itself was pretty easy to get the hang of, and once we did, it was insanely fun. We were the last ATV of the group and Lee never let us fall far behind at all and was always there to check in on us and encourage us. The trail itself is very entertaining and had awesome views of the Red Rocks - there were some rocky portions that seemed tough at first but once we got the hang of it we were having a blast.
I think it's important to remember that you will have absolute mounds of dust all over you after your experience is complete, so please do not wear anything too nice. After we returned to the building, Lee was kind enough to creatively un-dust us with some leaf blowers which also provided an entertaining twist to our journey.
Honestly, I think this experience was totally worth the money, and I would totally do it again. As I said, I was pretty scared as I'm not the biggest adrenaline junkie out there, but we just had such a great time and left with a big smile on our faces. Though we were lucky enough to ride with Lee, the other guides Donnie and Mike both seemed really cool and nice as well. Great vibes. 10/10 recommend.