I went to all of the prospect tourneys from 2015-2018 because I was living in Buffalo at the time. It's a fun novelty, me and my brother had a good time, but the quality of hockey was absolutely dreadful.
It's a bunch of teenagers ranging from elite prospect to glorified beer leaguer, who have never played together and don't know any system, who are all playing street hockey with each other. Most of the good prospects only play one game or two. It was cool being able to see Nico, Zacha, Wood, etc before everyone else but they aren't going to "show" for you, if that makes sense.
You'll see a lot of the guys there, though. I saw both Shero and Castron. Langenbrunner and Pandolfo were both with the Bruins brass at the time. The Sabres usually have Marty Biron as color commentator for the event, I bumped into him and got to say him. Anyone who has ever met Biron knows he's the nicest guy in the world, very chatty and always smiling. He's always happy to stop and say hi to fans or get a picture.
It's fun to make a day out of, though. The Harbor Center is a nice facility and there's some cool stuff to do down at the water front. There's some historical sites including a preserved WWII battleship, the USS Sullivan. Some good food too. Iron Works, Cobblestone, Southern Tier Brewery, lots of really great spots near the arena. Swannie House is a nice dive bar if you want a greasy burger and cheap beer. If you're not afraid of walking you can head down to Resurgence on Ohio Street, one of the really popular local breweries. The Buffalo Bisons stadium is in walking distance, they are the minor league affiliate of the Toronto Blue Jays if you want to catch a baseball game.
People will tell you the best Italian food in Buffalo is at Chef's, but I disagree. Go to Mulberry Italian Bistro in Lackawanna, it's only about 10-15 mins south of the arena. It's supposedly a Brooklyn style Italian restaurant, but you Jersey boys would know that better than me. All I can tell you is that the food is f***ing bomb. I recommend the chicken parm.
Also - for those of you that play Pokemon Go, Canalside is legitimately one of the best places in the world to play. Gyms, spots, and nests everywhere.