What seems to come out of all this is that IL4 600s are better when going very fast, and twins are better going slow at low revs. Well I know what kind of riding I do around Birmingham, so the SV suits me perfectly! Its the grunt I need to just flick open the throttle at any rev range and catapult past that annoying 4x4 from 30mph to 40mph. When I upgrade, I'd still want the great twin sound and power delivery, so just get a bigger twin for me
. I would love to try some of the IL4s though, but it is a totally different riding style I'd imagine, as the GSXF-750 I tried seemed pants the way I rode it.