In as much as we've not tested this specific system or that bike, there's not much we can say about this stuff except two thngs:
1. It looks terrific.
2. Leo Vince kit we've bolted on other bikes has shown decent power gains and has been well-made.
So, go figure, as they say (apparently) in the US of A.
Here's the press info:

"Following on from its successful CBR1000RR exhausts, LeoVince has announced these new slip-ons, plus the optional decat, for the CB1000RR.

There's a choice of SBK-GP at just £277 incl vat, and the SBK-Factory, in titanium, for £430 incl vat. Both these exhausts are slip-ons and can be fitted to the stock catalyst.

The SBK-GP sports a special shot-peened effect, easy clean finish, and the can is a very short & stubby 37cms in length (14" in old money!). 'E' approved and road legal, with removable db baffle.

The SBK-Factory is available in a titanium casing with carbon tailcone, or titanium with a complete carbon fibre outer / tailcone. Slightly shorter than the GP at just 35cms in length, the Factory cans give a deeper more bassy exhaust note, and are incredibly light...shaving 50% off compared to the standard can / cover. 'E' approved with removable db baffle.

For those that want more power, and a throatier sound, LeoVince have done the right thing and designed a SBK-Decat conversion to eliminate the catalyst. Manufactured in 304 stainless, this is a 2-into-1 layout and simply bolts onto the stock headers. The de-cat is designed to fit with the stock exhaust, or SBK slip-ons. Price £173.00."

Contact:MOTO.GB
Tel : 0845 094 1934 or email Leo Vince in the UK on sales@moto.gb.com

www.moto.gb.com