I wouldn't subscribe the statement that the 1653S offers bad burning quality at high speed!
You'd rather say it seems to be picky about which media to use. That has been stated elsewhere, too.
My latest burn at 16x on Verbatim 16x/MMC 004 printable surface media gave me excelent results. Burn finished in about 6 Minutes for a full disc of video (if I remember right). The burned DVD was even printed on the other side with a Canon I865 prior to burning.
Reading results are great, and reading the disc at omnipatched 12x instead of the stock 8x seems to work without flaws as well.
Tomorrow I will try to burn a Verbatim 8x/MMC 003 at 12x and 16x and let you know the results. Burning it at 8x gave me excelent results, even at 12x reading speed everything looks great!
Even on a cheapest no-name 4x media (even manufacturer unkown) it burned flawless at 4x and let's me read the media upto 10x. It surely looks far worse than the Verbatim and has some serious problems when reading at higher speed, but it's still within the specifications of what a good burn is (PI max<=280, PIF max<=4).
Maybe I'll try to burn those at 8x, too. But I don't expect any great results.