From what I'm reading, the fireworks show will only happen at USF after July 4th. Quote from Screamscape.
"Orlandos biggest fireworks show will return to Universal Orlando on July 4th at 9:50pm with pyro lighting the skies over Islands of Adventure, Universal Studios Florida and Citywalk. From July 5th to August 13th the fireworks will continue nightly at the Shooting Stars Fireworks show takes place nightly at 9:50, launching from the Studio Lagoon."
They don't mention anything about the show at IOA after July 4th. If that's the case, anywhere along the USF lagoon will be good. Just depends on how fast you wanna get out of there once the show ends. I've never seen the USF show. Does anything happen in the lagoon like the IOA show, or do all the fireworks go up?