DD spares no expense in the quality of parts and construction of their subs. They offer tons of options and hand build each sub. This is expensive and you have to pay for it.
If money is no object DD is the way to go. If you don't have the coin then AQ is a very good way to go. The AQ copper series subs use the very best parts and construction methods available off shore and are priced to reflect the cheaper build cost available in China. The HDC3 aluminum coil versions are hand built with American glues, spiders and coils and prices reflect the increased build costs.
AQ subs with the exception of the aluminum coil HDC series are built and priced to compete with subs built offshore or assembled from off shore parts the same as the majority of subs offered in todays market.
I have build both subs for years and I would always buy the DD if possible. There are some things the Chinese just don't do as well as DD and attention to detail is one of many, that's why we do final assembly and QC each AQ sub in "house". There are also some things AQ is not going to share with our Chinese partners; that's why we build the HDC aluminum coil versions in house and use American glues, spiders, coils and our own assembly methods.
Lets face it, if you teach the Chinese a new trick they quickly sell it to everyone else and quicker then you can blink your eye a lot of subs start looking like yours, at least on first glance.