We did the 3 day CitySights NY Hop-on Hop-off. It is a wonderful way to see the City, especially if you are pressed for time. We do this in all the major Cities we visit if it is available.
We would not go with this Company again. The main reason is that their buses do not have a downstairs area to sit and it is not covered for the rain. I was traveling with 2 seniors and they were very uncomfortable climbing the stairs and having to sit in the rain. Ponchos were given out thankfully - but that didn't help from getting wet when it decided to downpour. The other thing I didn't like, was the fact the Tour Guides CONSTANTLY told us to leave them and the driver a tip. The more they harped on it, the less likely we were in the mood to leave that tip! It amazes me that each Tour Guide has a different stat to say when going by something. An example being - going through Times Square, 1 Guide says there are 500,000 people that come for News Year Eve - another says 1 million and then another says 250,000. Which is it?? I do enjoy when the Guide has a tidbit to share along the way outside of the usual information. There were 2 Guides we didn't like because they were not in a good mood and it showed. We hopped off the bus we were on and caught the next one.
The Tours themselves are great and as I said before - it is the best way to see the City. Do exactly like it says - hop off / hop on - stay as long as you want and then a bus is there about every 20 minutes to pick you up.