I did this tour only three days after a one and a half hour helicopter tour over Lake Mead, the Hoover Dam and the Grand Canyon in Nevada, so you can imagine that it is nearly impossible to find it as positive an experience as the former one!
Putting all biases aside though, please be aware that the ride takes about 15-20 minutes from lift off to touch down and for obvious safety reasons ONLY takes place over water. Also, it does not circle the island but only goes up and down the Hudson river.
I am generally a very positive person but I cannot avoid mentioning the REALLY, REALLY long wait in the company's really hot and humid lounge. People were coming in and out all the time, and it was obvious that the air conditioning could not really cope with that big space and all those people going in and out.
Comparing it with the amount of time you have to wait, you can imagine that 15 minutes is not long enough to compensate for the waiting time.
However, if you really want to get a good idea of the geography of the place, especially if it is a clear day, and want to see all major landmarks in Manhattan and the surrounding area, you should probably go on this tour.