I've been wearing Vanson separates, but I'm about to pull the trigger on a set from AlpineStars (MX1) one piece. I want full connection between the top and bottom. The Vansons have three short zippers, but in the event of complete wipeout, I dont think that's good enough.
As long as you're protecting yourself, get something with hard plastic armor on the elbows, shoulders, knees and a good back protector. I understand the pro's wanting less rather than more. The want to be in skinsuits pratically for mobility and weight. But *****, we dont make our living doing that and it'd be a drag to get seriously hurt doing something like a track day.
As far as recommendation, you need to try a bunch of suits cause they differ dramatically between manufacturers in my experience. You might look at some of the Motard suits out there since they are cut for more upright riding position suitable to the Speed Triple's position.
HelmetHarbor writes a lot of stuff about track suits and why they like a particular suit over another.
best,
kjazz