Worth it for $900?

If you want a lightweight aggressive aero bike it’s not a bad deal. Those wheels are expensive to buy separately. But keep in mind that resale will be tough. Rim brakes and older drivetrains will be a slippery slope, that bike won’t be worth $500 after a season or two. Cycling trends are like trade winds, and the disc brake-12 speed jet stream is what riders are swept up in. But bottom line is this, if you love the looks of it and because it looks cool you’ll ride more then by all means buy it. I’d give the guy $750 and spare him the disappointment of that bike staying on local classifieds for weeks to come.