My ds8 uses one. We just recently switched from Cozmo (which we loved) to Omnipod (which we are very excited about) because they have discontinued the Cozmo.
Regardless of which pump you choose, you will LOVE it. Honestly. They are all great and all have their little differences. The best thing to do is to call each company and have them send out a rep so you can touch, feel, play with, explore, etc. each pump. We had narrowed our search down to the big three (Minimed, Animas, and Cozmo) and had an idea of the ranking of how we liked them--Cozmo was dead last on our list. Then we met with the reps and Cozmo soared to the top. I didn't like Minimed because all their rep did was put down the other pumps, he didn't tell me why his was best. Animas was our second choice and seemed to be a good fit for what we were looking for, but Cozmo had several benefits that were exactly what we needed since ds was only 5 at that time.
At that time, I had no interest whatsoever in the Omnipod, but after living with disconnecting for swimming for two years, I'm ready to NOT have to deal with that. Even though a pump claims to be waterproof, I wasn't willing to risk putting it in a pool for two hours. I love that there's no tubing to get pulled, caught, or kinked. The pod itself does look big on a child, but the smaller ones will be available in about a year. Ds has worn a demo and it doesn't bother him at all...much better than his old pump hanging off his pants. Finally, the absolute BEST thing about the Omnipod was the site change. Ds pushed the buttons himself and said he did not even feel it. That's huge since we have been using the Emla cream to numb the site for all of his previous site changes. That makes the process sooooooo long!
Sorry to have gone on for so long! Bottom line: meet with the pump reps and handle each one you are interested in. That's the only way you are truly going to know what you like. You can't go wrong! You will love pumping. We sure do!