The prison carriage is a great little set. Most of the draw comes from the great minifigs and accessories.
The armored torso on the lion knight is incredible and leg printing to match. This fig is not very customizable but it just looks great. I would never want to cover that up torso with Euroarmor. The prisoners torso is the most versatile of the bunch and a change in arm color can make this guy part of any faction you would like. I like the head printing and two of these are completely new to the castle line.
The accessories... The great helm with red plume and black spear I really like. A shield from each faction! The helmet with neck protector and a sword in dark metallic grey. Yummy! The horse, the barding, and horn are fantastic. The only accessory missing in this set is a saddle for the horse to increase playability.
The carriage build is rather simple and has really big flaws for holding a prisoner. There are no bars between the cage and the guy driving the cart. Maybe you can put the screaming head on the driver and his head on the prisoner who is choking him. Or perhaps he will just climb right out of the top. Now I understand making a proper carriage at this price point is probably impossible, but... all of the flaws in the carriage design could have been covered up by just including a pair of handcuffs. The open design would not matter if you cuffed the guy to the bars. Why didn't TLG think of that? To TLG: I am available for consultation on future sets.
The parts included are great for MOC use. Mostly made of plates this is a great set for small pieces. You can never get enough of the telescope in dark brown, flames, or dark green wedges for landscaping. The gold cheese wedges are new and perfect for dressing up those old crownie strongholds! The modified brick with clip in dark green is new as well, not as useful perhaps but new all the same.
All of this in a $10 USD set. Fantabulous IMHO and a good value since decked out figs go for $3 a piece and horses for $1 or more.
Overall I would give the prison carriage a 4 out of 5. I, of course, will be buying in multiples. Enjoy everyone!