I like the viper
https://looksolutionsusa.com/products/viper-nt/
huge output. We use it at work for testing fumehoods. First time I tested it I was in our lobby with a door to the outside and a door into the lobby. 5x5 space. Had trouble finding the door and when I vented it someone called the fire department. Can do a stadium. You can also dial it down to reasonable.

