I have the EXO-500 and love it. I was actually at my dealership a few years back looking to buy the Shoei Qwest helmet and the sales guys talked me into the Scorpion because I would get more 'bang for my buck'. I've had it 3 years and while I need to replace my visor (because I must have washed it with sandpaper), it has held up very well and I would gladly go back in time and buy it again.
After buying my EXO-500, the wife picked up the EXO-1000 for some crazy price on the interwebs. While the 1000 is a nice helmet, I don't care for it as much as the 500. For me, it comes down to the vent placement. I think they are kind of awkward to use on the 1000. Also, fitting a Sena Headset to the 1000 was a little more challenging due to the way the liner fits together.
If I was in the market for buying a new helmet, I'd be looking at a modular solution. I always balked at the idea of a modular helmet until I went on a road trip with a a few buddies that had them. Nothing like pulling up to a light, flipping up the lid and yelling something at the guy next to you and have him be able to understand what you are saying (partly because they can read your lips). For the reason of pure convenience, I'd be looking at the EXO-900X. For $200 you get a helmet with all kinds of fancy features.
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