If you're not going to burn faster than 8x, why do you need a 16x burner?
I think you should avoid cheap media - it is the media that is most likely to fail, and why would you burn something if you don't want to keep it? - but of the media you listed, I like Ritek the best. 4x Ritek media (with the RICOHJPN code) is awesome and will burn at 8x. I have a bunch of it..
As for burning, I have two old 8x burners, one a Cyberdrive DX082D, which burns exceptionally, and a BenQ DW800a, which burns very well but not as well as the Cyberdrive, but it does quality scans and the Cyberdrive doesn't. So I keep both.
If you insist on a 16x burner that can burn dual layer media, you should get the BenQ DW1620a as it is the cheapest exceptional quality burner you can get. Flashing the firmware to the latest version will give you a 16-4-16 burner with 4x DL capability.