The newest Topline 4 600's from Honda, Suzuki, Yamaha & Kawasaki (CBR600RR, GSX-R600, R6 & ZX-6R) are all much more track-oriented nowdays than they ever were before... Depending upon your size they may, indeed, be a form of self-inflicted torture.
The so-called "2nd Tier 600's", the Kawasaki ZZR600, the Honda CBR600F4i, etc. are actually just lightly modified hottest models from a previous generation. These are all, still BLINDINGLY fast, handle like champs, unbelievable brakes, etc. Just not the latest & greatest versions.
The new 675 Triumph Daytona triple is a different fish, very sophisticated, light, etc. Also costs $9K.
The Suzuki SV650 and the new Kawasaki NINJA 650R are, as you have previously opined, also a different type of ride than the 600's, Top & 2nd Tier: more of a modern STANDARD STREETBIKE than a "Rickey Racer" squid-type wheelie-ing down the freeway at 60 mph. 12 second quarter mile times ain't that slow once you really think about it... You really should get a test ride on both of these: they are more comfortable, better gas mileage, etc. than you would imagine.
The Suzuki V-Strom 650 is very highly regarded in the real world: it kind of cuts the difference between true Dual Purpose bikes like the KLR650, the DR650SE, DR-Z400S: more of an adventure/touring bike than truly off-road capable.
The Suzuki DR-Z400SM (as in "Super Moto") is a lot of fun on the street if long distances are really not in the picture: you wouldn't want to ride to Atlanta on one with a passenger!
You can kill yourself very quickly and painfully on any of these bikes as their performance limits exceed anything reasonably needed on the street.
If it must be a sportbike I would suggest you buy an older 600, the cleanest, lowest mileage UNMODIFIED original one you can find. The Honda CBR600F4i is thought by many to be one of the best overall street motorcycles ever produced. I see them in the Cycle Trader and in the local paper for $5K. You could ride coast-to-coast on one of these babies in a heartbeat. They are probably only good for 100K miles or so if unmodified, unwrecked and properly maintained.
If you buy the right bike at the right price you should be able to ride it for a couple seasons and get most of what you paid for it back if you decide you really want a newest, greatest 600. You'll also be in a position to be more ready to actually safely use all they can do.
The new liter bikes can kill an accomplished & experienced street rider in one corner...
Good Luck!
