The positives - each castle has it's own distinct charm and attraction. You get time to explore each and it's a long day excursion (12-13hrs) so you get a lot for your money.
The negatives - the guide will try to aggressively sell you entrance/experience tickets at hugely inflated prices (more than double the gate price). The guide may also get quite abrupt and rude with you. Stay strong. You can visit the grounds of Pelés and Cantacuzino without paying an entry fee. You're only paying to go inside for an "experience". Personally we were happy with seeing both for free. There were extensive grounds to explore in the alloted time.
We were told that Bran Castle would have a 1hr queue so if we didn't buy the guide's offer (420 Lei for that single castle) then we wouldn't get in. We happened to arrive after 5pm on a Friday and bought our own entry ticket on arrival with no queue (200 Lei - 100 per person). Different to the other castles, you cannot visit the grounds of Bran without a ticket. Your choice, but we were happy with our gamble on this occasion and it payed off for us.
Lastly, the 3 entry prices quoted on this app (100 Lei, 70 Lei and 70 Lei) are out of date. Check online beforehand.
One other thing, we had free cancellation until midday before our excursion. At 12.02 (2 minutes after the deadline, quite deliberate in my opinion) we received a text message to say Pelés Castle was fully booked and they would take the group to the smaller Pelisor Castle (and still charged more then double the full cost for Pelés Castle). Both are in the same location, so while the group paid and got a worse experience, in my opinion, we paid nothing extra and had a great walk and lots of photos from the grounds.
In summary, I was prepared to give this a 1 star review as the guide was very aggressive, the organisation beforehand felt shambolic and the prices quoted were frankly a rip off. However, we enjoyed the castles. It was a great day and the experience won us over
