I had a well-farkled 2000 KLR650 (my brother/riding partner also has a KLR). I loved it, but I wanted more power, less vibes, more comfort and better highway manners, but I did not want to give up dirt road capability. A long time motorcycle enthusiast/mechanic told me to look at the wee strom. That got me looking at more bikes to include the KTM Adventure, Caponord, Ulysses, GS, Stelvio, Multistrada, etc. After a year + of research, I waffled back and forth between the 'Strom and Ulysses, until Buell went under.
I intended to get the 650, but found a decent deal on a 2007 1000. I got luggage, crash bars, windshield, madstad and Zumo 660 for it. I was very apprehensive about the bigger bike and the dirt roads. I am super happy I got the 'Strom. I can't believe how much better it is on the highway than the KLR, and I can actually sit the saddle for more than 20 minutes at a time.
I took it on a dirt ride, following my brother on his KLR. I was able to go everywhere he went without too much effort. And, when we both stopped, his legs were as tight as mine.
I try to stay away from the Vee vs. Wee pissing contests, because I like the fuel mileage and better off-road manners of the 650. I am happy I got the bigger bike, however, due to me carrying a decent amount of weight (me and luggage). Many people say it is more stable at higher speeds mixing it up with other traffic and/or higher winds as well.
If you do much good-road riding, I think you will love the 'Strom. I couldn't happier with my decision to get one.
Best of luck! - M