There are two main things you should bear in mind when purchasing and using an inflatable pool slide.
Safety
Most important of all is safety. The pool needs to be deep enough at the end of the slide to ensure nobody hits the bottom of the pool. 5 feet is normally sufficient, but you should follow the guidelines that come with the specific product you are interested in. Children should always be under adult supervision when using the slide.
Design and Construction
Whilst some slides can be used with both above-ground and in-ground pools, others are specifically designed for one or the other, so check before purchasing. It’s important that the slide is stable, and for this reason most models allow you to fill the base with water. As with most things in life, you get what you pay for, and models at the very cheap end of the market may be a turn out to be a false economy. A bunch of excited children bouncing up and down on the slide will soon cause rips or holes in poor quality materials, putting an untimely end to the fun. So it’s best to spend a little extra on a slide that will last. An example of a reasonably priced, but good quality slide is the Intex model.
There are a lot of designs on the market, from simple slides a few feet long to mini water parks. Bear in mind that the larger models will be harder and more time consuming to setup, and of course to dismantle and store.