Very easy to attach to the existing saddle. And really comfortable. There are a few less expensive models but it is worth paying a bit more to save this important part of your body.
After some bum-numbing excursions on my new road bike I just had to find something to ease the discomfort - padded cycle shorts didn't cut the mustard but this baby is fantastic. Easy to fit, with a drawstring to tighten on the saddle, the gel just makes things oh so much better.