Popular, go early. Arrive before 8:30 am if u want a quiet trail and good parking on the weekend. Hiking boots recommended but not necessary. Went on a Late Sept. saturday morning at 8:15 from the middle of the trail. It took two 30 year old semi-fit women 2 hours to do part A (1.7 miles). Up and down and rocky. Another hour to see the outlook of the Great Falls was nice, too but its probably not that 'Great' if you've seen other places.
The views are amazing. Hike/trail is very rocky and with people all over the place it can be difficult to find your next step. I'd say it's challenging compared to other hiking trails in the area. Definitely worth it if you live near by. We paid the $10 to park in the park instead of nearby roadside pulls off. $10 is good for that day plus next two days if you want to go back. They do take credit cards.