What‘s good about them? What‘s bad?
Engine stall - the engine will stop firing and need to be restarted. You can stop without changing down, however this is not good practice as you should always be in the correct gear for your speed. When stationary your bike should be out of gear. When pulling away from stationary you should be in first gear. Otherwise you will need to slip the clutch to avoid stalling a motorcycle, esp in heavy traffic. Effiecient motoring is about beingin the riht gear, third is not the right gear for pulling away in. When you stop, you shut the throttle, this is often automatic as you are pulling on the brake lever. At tick over a bike in say third gear will not be revving high enough to pull away at tick over, (generally), therefore the engine will (or may) stall.
You can pull your clutch in and brake if you need to stop depending on how close you are to the traffic lights when they turn red. If you can change down as you are stopping it's an option but the important thing is stopping safely. practice your emergency braking remembering 70%of your stopping power is in the front brake, you do not want to lock the brakes up if you can avoid it, keep the bike upright when your braking hard. If you see the lights are going to change giving you time to react safely, you can use your gears to slow you down quite rapidly but you will need to practice. Use you clutch as much as you can when you change gear once you've been riding a while it will become a natural reaction and you won't have to think about it.
I have not ridden one, but I have sat on one; trust me, get the Versys instead!! So much more comfortable, better looking, better handling, about the same power I prefer it x10.
My husband has one and loves it. It doesn't sit as exaggerated as a sport bike, but isn't as straight up as a touring bike (this is one of the big reasons he picked it). It's comfortable for long rides and is fast enough. It's too tall for me without modification, but I'm 5'3. My husband is 6'4 and the stock bike fits him fine. It's also comfortable for us to ride two up.