Beta has same motor as the RFS motor in KTM up to '07.

If you want more of a supermoto I'd get the SMR and spend $300 on lighting and a high output stator. SMR comes with SM tuned suspension, radial mount FTE front caliper, Braking wave rotors, steel braided brake lines, and a more aggressive cam than the EXC.

If you buy an EXC and want it to be more supermoto oriented you can count on spending $700 right off the bat for springs/revalve, atleast $500 on wheels, atleast $500 for a good brake set up (can get away with just a cheap used 320mm rotor/caliper relocator for about $150). And it still won't be near as good as an SMR. Depends on what you want to do with the bike. Any dirt?

Too bad you weren't looking 6 months ago. I sold a Husaberg FS650C for $3k. Had hi output stator, e-start, and came stock with same suspension and brakes as an SMR.