Hole in the Rock is definitely a unique, natural wonder! I think it's a great experience and doesn't take a huge commitment to go visit. Really though, it's a 5 minute walk from the parking lot up to the hole. So the overall trek is fairly quick and therefore great for those less inclined to hiking. But it's cool enough that any adventure-seeking person will enjoy seeing it up. If you've got family or guests visiting, then this is a clutch, easy experience to take them to.
Another neat part about the location is that it's next to a nice park, the Phoenix Zoo and the botanical garden so there are plenty of other things to enjoy in the area.
Tip - there are two different paths to get up the rock. If you're looking at the rock from the parking lot, the path around the right side has rocky stairs, and the path around the left has a more gradual incline.