It's solid investment. They may get a solid striker out of the bunch. All of them have youth on their side but none of them seem potential world beaters. Berardi possibly the best of the bunch though.
Indeed.. Gabbiadini showed some excellent form in Sampdoria's preseason, showing some stark improvements from his tenure at Bologna. If he manages to keep up his current form (having already scored a goal in two games played), I'd say there is a possibility of him becoming a breakout star this season in Serie A.
Simone Zaza also proved himself to be quite the interesting prospect in Ascoli last year, and while Boakye undoubtedly has talent, much of the hype died down last year when he didn't meet the massive expectations initially set in his debut season with Sassuolo on loan from Genoa (before his purchase by Juventus).
Immobile can really go either way; I can see him becoming a consistent player in the future, but there is the possibility of him flopping out next year as well. I doubt that Juventus really have any hopes for him at this point, with him similarly unable to meet the expectations set in his breathtaking season with Pescara during his Serie A debut with Genoa.
Imho Berardi, however, is a talent, possessing the potential to be really world class, if managed well. He's got very strong technique, and Juventus have a wonderful asset tbh for their future, and even the future of the Italy NT. Shame that Inter couldn't snap him up beforehand.