I love my SV 650 so much. But I ride with my girlfreind alot and it really starts to lag with two passengers. I've been thinking about upgrading to either a GSX-R 750, or a 929rr. I'm just wondering if what you guys think, is that too big a step or should I get a 600 for awhile. Keep in mind I do alot of two up riding and I've been riding for 4 years now. Also any other suggestions for bikes that are good for two up. I know I want something more sport oreiented than the SV. Thanks guys.