I would recommend that you download and install the trial. It is a full working version that will allow you to try it for 90 days for free. If you don't like it, remove it. If you like it, either pickup a retail copy and activate with the key or pay be credit card.
It has been my experience that support will let you cancel within the 30 day period after purchase without a hassle, unless you count getting to support, which can be a hassle.
-steve