4 stars because of the site set up--site doesn't make it very clear whether p/u from the hotel is an option or not (I've sent an email and then later made a call to the company trying to clarify, but it did not help either). Anyway, the website allows you to put the name of your hotel in for the p/u when in fact you have to wait for the bus in front of the Empress. Other than that everything was fine. We took the tour twice, once for the tour itself and the other time we've used hop-off/hop-on option. The best guide was Adrian, he loves his city and we just loved his sense of humor!