There is very little difference between the 2166D and the 2164D apart from lightscribe ability. Both drives are virtually identical inside except for one small part used for the lightscribe labelling process.
As for region free writers. There are no such things as region free DVD writers. The drive manufacturers are forced to put region protection in, or else they will not be allowed to produce DVD writers. That was apparently one of the conditions that was laid out to them by the people who control the DVD standard. So they have no choice in the matter.
If you see any writers on sale in shops which are region free, chances are that the person running the shop is flashing the drive with hacked firmware which is region free. I purchased a DVD-ROM drive that got this treatment once. The advertisement said that the drive was region free. When I purchased the drive, the shop owner told me to wait for a few minutes, then plugged the drive into a computer and flashed it with hacked firmware there and then.
Some writers, (e.g. Lite-On ones) have 3rd party utilities (not from Lite-On) which can disable region protection on the drives. For LG writers, we have pretty good hacked firmware support for virtually all current models (but not the E10L as that is too new), thanks to The Dangerous Brothers (http://tdb.rpc1.org).
It's normal for LG to release new models without updating their websites. The H10N has been around for quite a few months in various parts of the world and I still can't find it listed on their websites.
Btw, no need to double post about the E10L. You already have the other thread for it.