UpdateHonestly people, I will
not recommend a short-bottle/long-bottle free-flow exhaust. Not sure about other free-flow silencers. The cocktail shaker exhaust sounds very good from the videos I've seen.
Anyhow, just did a few runs with the Silman Short Bottle on. Firstly dad rode the bike and I tried to hear the sound properly, and then I rode the bike and dad had a listen to it. At lower RPMs, it is a great thump, awesome Bullet sound. Till a steady 50km/hr is bearable. As soon as we give it a bit of throttle or higher RPMs, it gets very loud and blatty. Instead of thump, all you hear is phat phat phat. Any amount of moderate-high acceleration releases an obnoxious sound. And at higher speeds I can predict it will be very annoying to the rider and of course other people. No respect for Bullet. I even tried the removable baffle from the EFI silencer in the free-flow one. With that, all you hear is air coming out the exhaust in a rhythmatic note - fuss fuss fuss.
I will easily switch back to the EFI Silencer without the removable baffle. It is not too loud and not too quiet - just decent enough. I don't have the Silman Short Bottle with baffles, but after listening to the video Singh_Chicago posted, I think it is decent. Any short bottle with some kind of baffling, i.e. perforated tube or glasswool type of material should be okay.
We can still run the free-flow, but it all depends on the person. If you like very loud and blatty sound from your Bullet, then go for it. Otherwise, as long as you prefer a decent thump throughout the rev range, please choose some type of restricted silencer. The EFI silencer does a great job. Yes it does get a bit blatty at higher RPMs, but not too bad at all. Maybe we can drill a few larger holes in the perforated tube of the EFI to make it more louder, but I think it is okay as it is.