Sorry for being one day late (..but I had to honor presidents here and take a day off.. ;)

The document was clear and I spotted no issues (bearing in mind my limited HTTP proficiency). I did also check the ext-value ABNF with a tool that it is correct (which it was).

The IDnits complains about non-ascii characters (pound, euro, etc). I am not sure whether that will turn out to an "editorial" issue in the final RFC text.