Take my opiniof for what it's worth, but I did not like riding the 1000. I love the 650, but the 1000 just didn't do it for me. I don't know what it was, but it didn't feel like it wanted to turn as easily as the smaller SV. Power was nice, but nothing like the 1000 cc inline 4s.
I bought a 03 Sv1000s over the 650. My reasons were I was coming off a vmax and I found the torque on the Dl650 to be anemic. As fr as I understand the Dl has stronger midrange then the Sv 650. When I test rode the Dl 650 I was very impressed with the bike as a whole and figured that the sv650 would be even better but when I got off of the sv1000s I just couldn't stop smiling. It was an absolute hoot, hence I now own one.
I4 litre class super sport torque.
I4 600 super sport power - DOWN LOW where it matters.
Dual Cans which look mean and can be made to sound meaner.
Unique because not everybody has one.
More power to be had with simple, low cost mods.
Does not look or sound like an I4 (see Cons).
Bloody uncomfortable in stock trim! (needs a corbin seat, heli-bars, & lowered pegs)
Rear shock, though fully adjustable, is not great for aggressive street riding or track use.
Does not look or sound like an I4.