That is a 640 unit. It will have a BETTER image than the FLIR PTS stuff. Also the Armasight units seem pretty durable. $1500 is a crazy good deal. It would be worth way more than that if there was still any customer service behind the product. Thats your primary risk, no one to fix it if necessary. Sucks that FLIR boned us all.
We have an Armasight 640 2-16x50, and I think it was about $4,000 new maybe 4 years ago. With a 75MM lens, the scope you are looking at was very likely more expensive than ours, probably around $4,500-$5,000 but thats just a guess. The lens is one of the most expensive parts.
The image on ours is very good. We've compared it to a Pulsar XG-50 that as a 12 micron 640 core like the Trijicons, and while of course the Pulsar is better, the Zeus hunts just as well, and I don't feel handicapped by it at all vs the Pulsar for coyotes. For coyote hunting, having a higher base magnification is your friend IMHO, so that 75MM Zeus would kick ass for calling coyotes if you ask me.
Honestly, I think you would have a damn tough time buying a better image quality for that price, period. My take would be...worth the risk!