I've been running a 14T front sprocket for 10,000 miles now and the gearing is perfect for me. Bear in mind I've got the 1100 though, which was definitely overgeared in stock trim, (you couldn't comfortably use sixth gear below an indicate 80). I don't know how it'll feel on the 796 so I'd be interested to hear how you get on.
As Albie said, the smaller front sprocket means that the chain runs closer to the swinging arm. I can see witness marks on my nylon swinging arm protector but, after 10k miles, there's still plenty of meat left on it and I think you'd only have to think about replacing it after around 25k. The swinging arm guard is easy to check, easy to replace and cheap to buy, so not really a problem.
While the better option, engineeringwise, would be a larger rear sprocket, that would also require a longer chain, so is a much more expensive option. If and when my chain needs replacing, I'll probably go down this route but, in the meantime, I'm happy with the 14T front.
If you've not adjusted the chain, two things to watch out for;
1. Don't overtighten the pinch bolts. If you overdo it, you can damage the eccentric adjuster. Torque them to 31Nm after applying some moly grease to the threads and under the heads. Tighten them in the sequence 1-2-1.
2. When you check the chain play, you're not measuring the up and down movement as you would with a conventional swinging arm, instead you measure the distance from the underside of the swinging arm to the centre of one of the chain pins. It should be 62mm +/- 1mm at a point equidistant between the two sprockets with the bike on the sidestand.
Note that, while the suggested amount of play seems very loose compared with a conventional swinging arm, when you're sat on the bike, the chain tightens considerably so don't be tempted to over tighten it while it's on the stand. Get someone to sit on it and feel the difference between loaded and unloaded.