Recommended Rucksack?

I have the same one as this, fits laptop in fine unless you got one of those huge fancy screened ones, plus a few other bits like work shoes/low top vans.

It also came with straps to strap it to tail, I'm not sure if it's designed for it but fits contour of the tank on my daytona 650 perfectly but don't know if I'd want those straps through my fairing near the engine

 

I have the Triumph one. Excellent. It was a tad expensive at £20,000 but I got a free Rocket GT with it