I personally think it should be open to SV650.org members.
Its nice when everyone is on the same bike, but, the SV has been around for a while & no doubt many of the members (or X members) who still post / or visit this forum from time to time would like to join in in the fun.
As I've recently moved to a bigger bike I'd still enjoy meeting up with people & doing track time. The SV is a cracking bike & can put bigger bikes to shame (trust me). From a newbie perspective I would say its the responsibility of more experienced riders to give input & help to anyone who asks for it. That's what I've always found at track days & have been grateful for.....
Looks if I go I'll be in trouble as I wobble around...........
Just my 50 pence worth....
D.