LOVED. IT.
Such a great option to get some outdoorsy into the city! I went yesterday (weather was incredibly warm) and it wasn't too crowded. We did tandem which was $21.50 an hour. The process is pretty quick. You walk up, fill out a waiver, and give a credit card or your license as collateral. Then, you walk over and grab a life jacket and paddles - and your off! The views are fantastic, everyone else who is kayaking is pretty mindful of not ramming into one another. The way the bridge are, it's also pretty easy to stay away from boats. I really enjoyed this and plan on coming back.
As a side note, there are lockers available for $1.00 an hour to keep items you may be concerned about bringing into the water with you.