I've got 4 drives :
- NU Tech DDW-082 (can scan PI/PIF/PO/Jitter)
- Liteon SOHW-1633S (can scan PI/PIF only)
- Liteon JLMS XJ-166S (can scan PI/PIF only)
- BenQ 1650S (can scan PI/PIF only)
and I have been scanning discs regularly. It appears that there is NO RELIABLE RESULT as what NU reports as 300 PI, Liteon SOHW1633s says 60PI and Liteon JLMS says 1200PI or nearby. BenQ reports in the 1000 PI all the time. Does anyone know which one produces the most reliable result because even the graph shape is radically different - and so far, the Liteon SOHW is giving results better than believable from my perspective. I would be inclined to trust NU (Phillips based chipset) but the speed is CAV :S confused...

I would use the LiteOn 1633. Nu drives are notoriously bad at scanning, and the ROM drive is equally unpredictable. But the main point is to avoid comparing scans from different drives, and stick to what ever you finally decide to use. The 1633 has proven to be a very reliable scanner for most everyone who uses it. I can't say much about the Benq, as I don't have one.

Some people say Plextor PX-712A is the best PI/PIF scanner, but I don't have any Plextor except some CD-ROM and CD writers and PX-708A which doesn't support PI/PIF scanning.

I've just flashed my Nu-tech DDW-163 which is a OEM BenQ DW1600/1620/1620A Pro and haven't tried any scanning.

Lite-On SOHW-832S/851S/812S have been good to me for scanning, but I no more have one. I once had three @832S. I used SOHW-1613S@1633S for PI/PIF scanning recently.

LG and Samsung DVD writers do not support PI/PIF scanning yet. Perhaps one or two Samsung models that use Mediatek chipsets support KProbe PI/PIF scanning but it does not work on mine.

Equally unavailable in Pioneer A08 and A05 I have.

DW1650S is available??

if you think the 1633S is good... then that means the <22 PI and <2 PIF meaasurements for my princo 4x@pinco8x01 6x is true? YIPPEEE!!!!

To add to the confusion: I'd trust a combination of LiteOn and BenQ, IF you find out that BenQ 1650S can produce repeatable results on a same disc (scan the same disc five times, each time inserting it again. Are the results very similar?).

Also, if you are going to read the discs in the LiteOn drive only, then trust the LiteOn. If you are going to use then in the BenQ drive only, then trust the BenQ drive.

If you are going to use them in unknown drives, scan in both LiteOn and BenQ

Perhaps you meant DVP-1650S DVD-ROM drive.

Well - i'm pretty sure I can't trust the BenQ cos after further scanning, even a *brought pressed* dvd-rom shows same scans over and over - 1000+ PI and no PIF and also spews out a couple of times with servo tracking failures ... even on good discs. I think that the Princo results seem too good to be true because a DVD-ROM slows down towards the end .... so I'm stuck with no clear path as to scanning.... I think I can trust my NU even though it's strange - it reports a 300 for the Princo and bowl shapes. Jitter is <11% and PIF are 4 ish. PO is non-existent ... sounds consistent with some of the other princo scans ... but it is possible that I can trust the liteon because using a speedhacked JLMS XJ-166S I get a smooth curve until it tops out at 16.2X and drops down to 8X-ish - anyone with better advice? This is sure confusing :S

dvd -roms are not reliable for quality testing, so unless you don't have a Benq Dvd rw don't use it for testing

Go with the Liteon SOHW-1633S (can scan PI/PIF only). I have an older model of this drive which works great when doing PI/PIF scans using KProbe2.

download cdbremse and lock the dvd-rom's speed @ 4x cav, then compare

how will cdbremse work? I don't think my firmware even allows speedsetting

It will work i dunno how it works, but get it from www.cdbremse.de
I have a 166s and it 'seems' to produce somewhat reliable PI/Px results but only when cdbremse locks the speed @ 4x or similar.

I scan at 8x more often than at 4x now.

8x is ... different for me -- way different