Need help Picking a new Sub!

What are the pro's & con's of the two;

High power, large excursion, lower efficiency

Lower power, less excursion, higher efficiency

I'll tell you what I think, but I'd really like for some of the board regulars (Haemphsyt and Steven K. come to mind) to weigh in on this.

What I think is this:  we've already highlighted the major tradeoffs.  It takes more of everything to produce a quality high excursion woofer.  (better design, better materials, better motor, etc.)  This costs money.  To control the extra movement also costs efficiency.  On the pro side of high excursion you usually buy higher power handling (which may lead to higher potential spl), usually smaller box size (not a concern in your situation), and possibly the ability to force the driver deeper in certain applications without running into mechanical limits. 

Lower excursion subwoofers are almost always more efficient, always seem to fit in larger boxes, run into mechanical limits earlier (obviously) which limit their flexibility in some applications, and are generally cheaper. 

It is very very important to note that within their thermal and mechanical limits high excursion and low excursion drivers can sound _EQUALLY_ good. 

I would buy high excursion if:

AND I both had the money and power for the setup to make sense.