I am certainly in the minority but this has been sitting in our backyard, rarely used. I can see how it would be fun but my 3 and 1 year old only had interest in it for about a week. I agree that the tower should hook into place. I also have a 5 year old and he has little or no interest. I'm thinking about putting sand in it to give that a try.
Great product, arrived promptly. Very durable, but make certain there are no sticks/rocks/debris under slide because they will tear the plastic. Be careful where you "aim" the slide - children, especially small ones, can get a lot of distance if the slide is placed on a slight hill, so check for clearance at the end of the slide as well as debris they could run in to.