hmmm, i have never noticed any buzzing- it was one thing i was concious of when buying because of owners reviews. in fact less vibes than my t3.
i can't say clip ons have bothered me. i've found that whatever on an unfaired bike something will 'suffer'. the bandit had a more s3 bar set up, which resulted in windblast to the chest, that could be fatiguing, the s4/t3 took a few rides to build up wrist stamina- low speeds are a little achy at first but don't notice it now. i feel more in control and 'at one' with the bike with clip ons.
also the low speed surge- don't notice it really. second nature now to use the clutch and throttle to smooth it out.
a cheaper suck it and see method would be raask bar raisers. they clamp on where the s4 clip ons go, require no drilling/expensive mods/top yoke removal. just bars and i would guess cables.
http://www.busters-accessories.co.uk...l.asp?prod=RAA