You have to buy an adapter https://www.bbqguru.com/StoreNav?CategoryId=2&ProductId=6 and install it in a lower vent hole. Use tape to seal the other two holes on that same vent and close the other two lower vents. They have install instructions for the adapter on their support page.
I purchased a party q and it didn't require an adapter. Works perfectly on my 22.5 WSM. Batteries last about 10 hours in cold weather. Haven't had it long enough to see how well it will do in the summer.
I have a Party Q on my 18.5 WSM and I did get the adapter. Installation was super easy! I am not familiar with the IQ10, but I can say my Party Q works great for me. I'm using rechargable batteries and I have no problems with battery life in summer. I used it this past weekend and I can tell you it works great in this particularly brutal So Cal winter!