Saw in their 6/2003 tech notes they are offering an O ring, (simular to a D-Fender I guess?) for Armalite owners with extraction problems.

Anyone get one yet? Is it a worthwhile upgrade? D-Fenders are expensive. Wolf XP extracotr springs are inexpensive.

I cured my Preban Eagle Arms extration problems by rebarrelling with a QPI brl.

I had read they were free to Armalite and non-Armalite owners as a courtesy from Armalite.  Ordered some, in July, to try but haven't gotten them yet.

They are infact free from Armalite to anyone.  I thought this was very cool on their part, a nice PR move.  I own 3 different extractor rings.  The D-fender, the Olympic Arms eX-ring and the Armalite O-ring.  When I add an O-ring to my extractor, it will be the Armalite.  It is the thickest and stiffest of the 3.  the D-ring is thin, but fairly stiff.  The eX-ring is thick but seems to be a squishy, low quality material, the Armalite is thick, tight and stiff, it appears that it will hold up the longest.  All of this is subjective (me playing with them, measuring them, squishing them, etc.), but the Armalite will be the first one I try.  When it dies I will try the other two just for comparison, then I'll truly see who the winner is, but that's a few years off probably. [:)]

I have had a D-fender in one of my Carbines for about 5 years. They are pretty durable.

My preferred extractor upgrade is the Wolff XP Extractor spring, stock insert, no ring.