I've generally made no apologies for my views on subwoofer drivers. I've established a set of criteria I use to evaluate a driver as a good choice in a home subwoofer. Some of those criteria may or may not have much merit in the real world. None the less, it has lead to a small number of drivers, mostly Pro audio, which meet my criteria. What I look for is a driver with at least 10mm of linear XMAX (assuming sufficient driver diameter) and preferably quite a bit more. A power handling that is in excess of 1000 watts. relatively low inductance for a subwoofer. A linear motor design which makes use of good linearizing techniques such as the voice coil itself, inductance rings, etc. Finally, that it be a high quality and well built driver, preferably one that can be readily rebuilt if damaged. Beyond that, I like good sensitivity, but using better terminology, one that can be designed to have high system efficiency at the frequencies it will be utilized at. Low distortion, including in the upper bass frequencies. This means that pro subwoofers tend to be the best options because they tend to meet these criteria for the least money, and in some cases, simply do a better job meeting the criteria compared to any driver. It was very validating when Ricci started testing these pro drivers and finding that the best of them could seriously kick some butt in the low bass department. http://www.data-bass.com/systems One criteria I require (as mentioned above) is low distortion. A number of high powered home theater subwoofers have very high inductance and do not have the most linear motors. These combine to create a driver that often has rising distortion not just as the driver loses its composure in the excursion department, but at higher frequencies as well. Many of these drivers has higher levels of 2nd harmonic distortion which is likely not so bad, but also odd order. This is more bad as it is more audible. Because the odd order rises, you also often see higher odd order distortion (5th, 7th, etc.) begin to rise, and while still very low in absolute terms, they actually exceed audible levels rather quickly (and would not be masked by content because they are higher order). This is why I like pro drivers as they don't typically suffer this issue, while handling a lot of power, being really well made, and easily rebuilt if need be. Add in great high sensitivity and you have a sub that is capable of a lot of output. The downside of these pro drivers as compared to the others I mentioned is typically two fold:much lower xmax, often 1/2 to 1/3 that of the uber subslower mms, higher BL, and a number of other factors that tend to favor a larger box and a more downwardly tilted response. So that's my preference and why. I'm not suggesting my view is right or the only way. It is simply my preference. I'd like to know what your preferences are and why. Now as for my favorite drivers (meeting all the criteria above):B&C 21DS115-4 (Current favorite driver at any price)B&C 18DS115-4Focusworks GUJ21v1Faitalpro 18XL1800Affordable drivers meeting at least some of the above criteria:Dayton Ultimax 18Dayton PA465s-8 (Very under-rated in my opinion, 11mm of xmax, 1000 watts rms, 2000 watts max power, 94db sensitivity, and linear motor)And....Promising mew driver lineLa Voce Subwoofers http://www.loudspeakersplus.com/LaVoce-Pro-Audio-Speakers-s/228.htmExpect some future articles related to La Voce drivers. I have already talked with Loudspeakers plus about coming out to their facility and touring the drivers once they arrive. Who knows, maybe more. These drivers seem to offer many of the things I love at more favorable pricing. So that's my preference and why. I'm not suggesting my view is right or the only way. It is simply my preference. I'd like to know what your preferences are and why.