Monster v's 999?
Cheaper to service (even less if NOT the S4R or S4)
Cheaper to fix after a trackday 'off' - as no plastic
Cheaper to insure (just about)
But - do you want all the plumbing on view? - some love it, some hate it, thats why I got an aircooled.
If ever down this way, you are more than welcome to have a test on my M1000sie - and am sure Webby would play 'ball' & bring his S4R over, so you could compare them
C