Both bikes are great!
But if you post this question in Orange Crush, you'll get a wider array of suggestions. Thumpers is for thumpers.
Personally, the 950/990 is better on more slab while being the top contender for liter sized bikes in the dirt. And if you're ever 2 up, it's the right choice. I haven't had wind buffeting be a problem.
The 690 is OK on slab but gets way more better when the slab is gone. There are some known issues to deal with but the bike is a classic. A Rally style fairing will remove the air flow issue, IMO.
Don't rule out the 500 FI bikes, the power to weight ratio continues to improve and they're much more nimble in the dirt. They will slab along just fine if you choose. I think that KTM is currently making the best line of dual sports and making it tough to say no to any of their offerings.
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