I bought tickets for my daughter and niece to see all the sights, hop on and off. Well, the sharks who sold us the 2-day tix at Times Sq said the bus passed every 20 minutes. We got in line and waited an HOUR during which time NO BUSSES CAME. The lines were very long. Finally got on. At the Seaport had to wait about 30 mins and then as a result missed the 'night tour' by about 15 mins. The next day waited 1.5 hours for the Uptown Loop at a designated stop while FOUR busses passed without stopping but there were empty seats on them. What's going on Grayline? They were so eager to push the tickets on us, but could not deliver what they promised. It was not easy. We never used the tix on the second day. Tried calling their office, waited on hold 45 mins, and was told to submit a complaint in writing and MAYBE they'd issue a partial credit. I say this is a RIP OFF. BEWARE. You can take the subway or taxi's and walk - just use their map!! While it looks like fun, the reality, especially in baking heat of summer in NYC, is more like biting into a bad apple that looks good on the outside.
Pros: convenient way to see major sights in short time
Cons: no busses came - overcrowded, rude personnel