I have had a whole host of DVD-Roms and DVD Burners from different manufacturers.
And like you I hunted for some months to find the best ripper for faulty DVD disks.
My reasons for this is that I buy a load of ex-rentals from Blockbuster (my local BB sells them at Â£1 a disk).
However most of them have read errors causing stuttering/crashing while playback on my standalone.
So I hunted for a drive to allow me to give me a repaired backup.
I found from reading around a fantastic review for the (then) newly released Asus 616A DVD-Rom drive.
I bought this from SVP.co.uk and tried a bunch of the Blockbuster disks that I kept around which were unreadable in my 3 previous Liteon DVD-Roms, A NEC and Benq Burners. Also the famous Aopen DVD-Rom drive (which name I now forget) which is what most people on CDfreaks said was the best reader of damaged DVD disks. I paid around Â£20 for this on Ebay second hand as it was at the time in 2005 no longer available brand new.
But I was amazed as the Asus read them all, that none of the others could, without the slightest hitch or slowdown.
I have had it for two years now and it is simply an amazing reader of damaged disks.
However like the above poster I also bought the Samsung 162C DVD-Rom (the one with the Kreon Firmware) and on rare occasions when the Asus couldn’t read a damaged DVD disk I put it inside the Samsung and this read them without a hitch.
So either of these two drives would be excellent IMHO.
Hope this is some help