Hmm, I don't mean to make my first post a bit negative, but I'm fairly certain that 'slip on' sound clip has been faked. If you listen to the 'standard' and 'slip-on' clips one after the other, they're the same clip, just that the second has been dropped about a tone using sound editing software. The startup 'rev' is the same, as I think are the up and down shifts. Unless the rider's really consistent - which I suppose is quite possible, but....
Anyhoo, I shall watch this space - as I'm interested in a new can myself - for as much as they offer good economy, they do sound a little quiet.
I spoke to the akrapovic importer in Australia today, (Gas Imports, Melbourne) slip on in both carbon and stainless are able to be ordered, they said to expect at least a 3 month wait (possibly up to 5 months) for delivery. I'm in the market for the carbon slip on, rrp $669 Aussie approx
re:Akro trying to pull something, those aren't the same clips. Listen to the downshifts. When they ran the stock, the downshifts were better coordinated with the throttle blips. In the clip with the slip on, they are not as well coordinated; they shift too long after the blip. Without the two clips running simultaneously, I agree that it's fairly difficult to tell the diff.