flynbulldog- thanks for your reply.What are you using either of these bikes for?
If you are an expert racer with a sponsorship and a team either would be a good starting point for a race bike on an unlimited budget, but in that case you would already know which bike suits your team's goals.
If you are a collector you should get both. but the SL is going to be a bit more exclusive in the long run.
If you want to ride it to starbucks to show off to your buddies they most likely wouldn't know what they are looking at or the difference between the bikes - the V4 might be more impressive. But an S would probably have the same impact.
If you are buying a bike to ride in any meaningful way both are wrong. These are race bikes loaded with extremely expensive exotic parts that will not live long in a street environment. Service will be stupidly expensive and riding along at 30 or 40 MPH will be torturous to both you and the bike. Buy a Pani S to ride and the Super Leggera to put in your office.
I’m not expert racer and would ride the bike mostly on the track