Use the Search Feature, it's been covered.
We all know how it is "supposed to work" and the idea behind it.
Like it's been said 1,000,000 times, it doesn't do anything.
It will not give you better response, it will not make more horsepower, it will get in your way, it could crack the intake boots.
Nobody talks trash about the stock crossover because they didn't pay any extra for it...and it came on the bike.
It wasn't labeled "boost tube" and sold for 15 to 25 bucks....
Truth be told, plug the holes with bolts, use hose clamps to make sure they're sealed, and make sure the bolt doesn't protrude into the intake path.
You'll never, ever notice a difference either way, good or bad.