Well in my garage right now is:
So I have pretty much all you are considering lol
Remember every bike will suit every rider differently. I love my 08 1000RR, which is my dedicated street bike, but does get to see quite a bit of track time.
If I were to do it all over again, I honestly don't know if my 600RR would be in the garage.
The 600RR, is an AWESOME
trackbike as you know. When I decided to make it my trackbike my other bike at the time was an 04 1000RR. So the choice was obvious and simple. The 04 1kRR was a TANK! And I was EASILY 3-4 seconds a lap faster on the 600RR than I was on the 1000RR.
But since, I have the 08 1000RR and can honestly say that the 08+ drastically closes the gap on the difference between the bikes.
My laps times between the 2 are nearly identical now. (but the 08 1kRR is completely stock, including the suspension setting) So you can see there is a LOT of room for me to play here.
But for the street I think the literbike is a no brainer (for me). But my history of bikes include: 04 1000RR, (2) different 02 954RR's, a 929, 96 ZX-6, 03 600RR, 04 600RR, 05 600RR, 86 Hurricane, couple cruisers, and the bikes that are currently in my garage. (and maybe a couple I am missing...)
For the DR-Z400, that bike is a BLAST to ride! Especially on the track. But for the street, not so much. At 70-80 highway speeds it is CRYING! And it's obnoxiously loud. But again a blast on the track.