Summary: A great time with some capable, nice people.
This will be slightly long due to our satisfaction with the trip.
The day before the trip we had seen two guides with some current clients behind the old walls of the city up near the abandoned village on the mountain behind Kotor. We were hiking, and decided to take them up on their invitation to follow their group to the top of the canyon route to see where they were going to start.
The next day, we were their clients. Yanko and Mishka (please accept my apologies for slaughtering the names' spelling/pronunciation) met us at 10am for our trip up to the canyon. We stopped by the same small terraced home where we met the day before, had some local juice, and then hiked down to the canyon river over the scrabbly terrain with the backdrop of the Kotor Bay mountains around us all the while.
What followed was a mixture of repelling down through over crevices and waterfalls, hiking around (and through) pools of crystal-clear mountain water, and hopping along rocks. The end involved some nice little jumps down into pools that were about 15 and 20 or so feet tall. Note: repelling down them is also an option.
I have had five years experience top-rope climbing in the appalachians, and to my relatively amateur eyes these two were more than competent and professional. Their instructions to our party were clear and informative. The harnesses were comfortable and the equipment in decent order. They knew the route intimately and the anchors in the rock faces were skillfully placed.
The other person in our group had only been repelling once and did just fine. As long as you're feeling a bit adventurous, even without experience, I think you'd be well taken care of.
Also worth mentioning is that the two locals were extremely personable throughout the entire trip. They were able and quite willing to talk about the local geology, culture, and history. This was one of the most interesting parts of our Kotor visit in its own right.
The price, for two guides, for as long as we were up there, is more than fair. I was saddened I didn't bring my wallet so that I could have given each of them a bit more.
If you want an afternoon to see some of the rugged and pristine parts of the Kotor area, this is definitely a good way to do it.