Audio Systems: dual voice coil subs, dual voice coil, flexability

Question
what is the pros and cons between using single voice coil speakers compared to dual voice coil speakers and vice versa, and also do they work better in certain types of boxes.

Answer
the pros to dual voice coil is simply a matter of flexability.  you can wire them in different ways to get different loads which can help get the most out of an amplifier.  especially when you have many subs.  if you are only runing 1 or 2 subs and are mostly going to just build the system and never change it then all you have to worry about is matching the ohms of the subs to your amp.  you can do that either with single or dual voicecoil and it wont make any difference for you.
There really arent' any disadvantages, a few manufacturer's charge more for dual coils so that's about the only disadvantage really.
as far as box type it makes no difference.
can I help with how to wire them or choose the right stuff for you?  Do you already have something and need to get more to finish the setup?  Let me know.  if you can include all model numbers that would help alot.

Good luck!