Anwig making AF+1 irrelevant is just plain wrong. AF+1 is still the best QD piece we have with "Enhances QD" and AGI+4. The AGI+4 as a WS modifier is also arguably better for Detonator than a ranged-focused Anwig and its extra R.Acc. It is true that the WS Acc augment makes Anwig the best choice for Slug. It's also a little more common to see a COR who doesn't also play RNG get the WS Acc and Ranged augments, meaning AF+1 isn't needed for Slug (in fact, I have the WS Acc and Acc/Atk augments on my Anwig, made primarily for PUP and MNK multi-hit WS - and even with one irrelevant augment, the WS Acc makes it my choice for Slug).
For Detonator I still think the RATT 5, STR 4 will be better than AGI 4, STR 4. And that doesn't even take into account the RACC bonus of the anwig which essentially allows you to drop considerable RACC gear elsewhere for STR (i.e. Alky's, warwolf, Rajas, Flame). Detonator is accurate but you still can miss it without reasonable accuracy.
I agree that the AF+1 is the best QD hat beating the AF hat by 4 AGI. Is that 4 AGI worth all those ancient beastcoins and months trying to get the items? Not to me. Anything that I can sleep, I have enough AGI already to do so. Things that resist sleep will do so even with max AGI. Any fight where QD is my major source of damage, I'm not really contributing that much to the fight to begin with other than rolls.
So its a min-max type of thing. If you have to be the COR with every slot maxed, the AF+1 is worth it to you as a QD piece. To me, I have little desire to maximize QD as its utility for most of what I do on COR is minimal beyond light based sleeping. Others may get more mileage if they do long kited fights. I don't. So wasting inv space and money to acquire this piece isn't a priority at all.