The itinerary is very good for an 8 day tour. I would have liked to spend longer in each location, but of course, you'd need to book a longer tour for that. The Plitvice lakes day was my absolute favourite and were blessed with a fine sunny day for it.
Bear in mind that this is a budget tour and the accomodation is not 5 star. It was however comfortable and clean. I would have liked more opportunity to eat 'regional' foods rather that most evening meals being in the hotels, but again they were more than adequate.
The local guides in each place we stopped were very informative. One thing I didn't like was that half our tour were English speaking and the other half were German speaking, so our tour guide had to give 2 commentaries for everything. It was a bit annoying I imagine even more so for the poor tour guide, who's native language is Croatian. Having said that, our guide was friendly and gave us plenty of history and information about different locations along the way.
All in all a fabulous tour. I would recommend a day or two before or after the tour in Dubrovnik so that you can get a better look around, it was a little rushed.