The tour of "Wicklow, Glendalough, and Powerscourt" is basically just a bus that takes you to the Powerscourt Gardens (which are truly wonderful - every leaf is designed to evoke a series of emotions and integrate seamlessly into a beautiful design) and the Glendalough site of St. Kevin's churches (my favorite part wasn't the buildings, but rather a stroll along a nature boardwalk on the perimeter of the property).
It is a nice itinerary, and it makes sense for solo travelers since the cost of the "tour" is basically the same as the cost of a rental car. The math does not work out if your party has two or more people. The tour does not include commentary, does not include the admission ticket to Powerscourt Gardens, does not include lunch (you make a stop at a mediocre restaurant in Einskerry), and Glendalough is free to everyone (50 cents for the informational pamphlet, again not included in the price of the tour). Richard was a great driver (but a poor DJ) and had some interesting things to say about blogs and sheep when he did decide to talk.
In summary, if you are traveling by yourself and want a private driver to drop you off at Powerscourt Gardens and Glendalough and pick you up at each after allowing 1.5 hours for you to wander around at each, this is a good tour. Otherwise you'd save money by renting a car and just driving your party yourself.
P.S. Definitely bring a coat of you visit in May - It's cold out there.