I have no experience with it.
But I'd not trust it if the ebay seller cannot write proper English:

Here is a picture showing the quality of the adjuster - you can twist it, but it will not brake!!

Click to expand...

FYI, I don't know of any adjuster that can brake, not to mention cannot brake.

Very Funny use of words -

Do you know anyting about Polyamide ? Supposedly this is what they are made out of.

From Wikipedia --> Polyamides are commonly used in textiles, automotives, carpet and sportswear due to their extreme durability and strength.

Could just be a fancy word for "plastic" -

Most of my E39 headlight adjuster info comes from this thread ...

Yes, thank you. I have seen that thread. Apparently the 2003 E39, which we have, has a different glue that holds the lense on that cannot be "baked" to open. There is a way to replace the adjusters but it is something I don't think i can do. I am looking into having someone do this for me but i need to supply the adjusters. I can't buy the aluminum ones right now, not in the budget. Hopefully the alternatives I found will work out.

For the amount of labor and work involved, I would not risk having to do it twice. Get the metal ones, a proven solution.

If you go that route, I guess you can be the beta tester and see if they hold up....but that could be a few years until we know for certain...

EAC Tuning will perform the job for you (2003 E39's), but if you cannot budget for the parts, I doubt you want to pay for their expertise/labor too.