I have a set of black 19s for road and have done 22000 miles on them. I use OEM 18s for track.
Cant tell the difference with either set on under light or hard driving. The Breytons are neither the lightest nor heaviest but frankly, in my experience having run BBS CHs on my last car, weight wise unless they are real lardy buggers, you wont notice.
Must say my BBS CHs were better quality in terms of the finish though. The Breytons are fine, the BBS were just excellent.
E92 M3, Breyton GTS 19s, black and carbon all over
Factory Mini John Cooper Works 211bhp
MK Indy R track car (road legal) 300bhp+ per ton, sequential box
VW Tiguan 4x4