Not to thread jack but am considering an SV650 as well...
I've only ever ridden my Triumph Street Triple 675. I have about 6 years/15k miles riding in the mountains before I did my first track day this year. I did one more track day and road in Intermediate group.
Going forward will be track only (no street) so I'm planning to go with a dedicated track bike. My goal is to continue learning how to track ride smooth/fast, while sharing the space safely with other rider's different experience levels and types of bikes. I'll mainly ride CMP and Road Atlanta, but will try to get to VIR, Roebling and NC Bike a few times.
My top two options I'm looking at are the SV650 and Triumph Daytona 675. I'm leaning towards the D675 since I know these Triumph's so well already (as far as maintenance/repair/sourcing parts), but it seems everyone recommends the SV to learn on, and can still be enjoyed by more experienced track day riders. I'm wondering if there's other reasons the SV is so popular for learning on. The D675 does have +50hp (might be seen as a negative for learning), but I'm not bothered by being passed by other riders even if they can only do it on the straights.
My only other concern is that shopping for a track prepped SV seems to be a little more difficult than the Daytona. I might be overlooking this, but it just seems all the SV's have been through multiple owners, raced, crashed, repaired, engine swapped, etc. Is that just the nature of these bikes being a little dated now and so popular, but nothing to worry too much about?