These are the ones that I put on my bike. They require no cutting, use no brackets, and are very strong (like the ones linked above, the bolts replace your motor mounts). They're a little more expensive than some of the others, but seemed to be the best ones I could find at the time.
I can highly recommend Vortex frame sliders (www.vortexracing .com). I've had them on my 636 and ZX-6RR. I also liked the Woodcraft sliders I had on my GSX-R600. Both brands sell replaceable pucks so you can buy just one puck if you need to replace one side, instead of having to buy a whole new set of frame sliders or you can change the color for not alot of coin. I have pics of them installed on my bikes so just let me know if you want me to post any pics.
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