I used mine without dampeners this weekend after getting two of them restrung.
I much prefer them with a dampener to be honest. I've gotten addicted to rubber band dampeners lately. But then again the 4Hundred/Smoke even with 20g added isn't the most massive thing around. However once the new strings broke in the sound got back to almost normal anyway.
I don't know why people bash the AG400 so much. Put some lead at 3/9 and a leather grip and it is a very good hit IMHO. Bone stock it has one of the biggest and sweetest sweetspots in its class according to the TWU tests. It has a very healthy twistweight even though the head is narrow and long.
With the Smoke version being on sale, I'm often times tempted to pick up a third one.
You know, I think I will submit a review on TW.
Chocobo, there is a new line coming out, some indications are it will be here before 2011. I'm hoping they bring back the 400 since they skipped it with the 4D lineup. 400G hotmelt, M-Fil 400, AG400, AGSmoke,.... no 4D