It has DVD9 quality in the sense that if this guy had put this transfer to a dual layer it would be about the same quality as it is now. It never says that it is a Dual Layer disc. The quality isn't only about space but also about how you use the space, so you can't really define DVD9 as a quality, you have to see it for yourself or let somebody review it before you can be sure about the quality.
It has DVD9 quality in the sense that if this guy had put this transfer to a dual layer it would be about the same quality as it is now. It never says that it is a Dual Layer disc. The quality isn't only about space but also about how you use the space, so you can't really define DVD9 as a quality, you have to see it for yourself or let somebody review it before you can be sure about the quality.