I have been doing car audio on a non comp level for about 18 years now. I am not a seasoned pro with changing times but I know how to install a good system, work out the kinks, and will not hook up anything for anyone without all the proper adaptors and hardware. I have been through many name brands. Alpine was a favorite for many years for all around quality for the price, have owed a couple 10's, 12's, and a type r 15. I have owned infinity 10's and 12's, fosgate 2 times p3 and power hx2 15's, jbl 15 wgti, sony xplode, old school oz audio, installed an old jl 15w6 back in the day, sundown sa-15, and more mid level stuff for other people.
I now have settled for the time being with my audiopipe txx-apa-15. I have been absolutely impressed as I didn't expect much out of this sub as I had not heard much about them. It was $140 and I figured id take a chance after blowing my alpine type r 15 of 4 years. Well it immediately out performed the alpine in the same sealed box made for the alpine. Months later I bought a sundown sa15 in a box made for it at a shop. Hooked it up to the same alpine mrd-m1005 1000rms amp. The Audiopipe was better in its sealed enclosure. I put it in the box the sundown was in and was even more impressed. Double output and nearly no distortion. I play bass tracks at high volume for 20 min and it pounds away with no issues. It is by far met my expectations. Hit 144.3 at the local shop where I paid $10 for a reading.
I am guessing that this audiopipe may outperform near anything in the price range of up to $200-250. I have tried to replace it twice and wound up selling the subs I bought to replace it(sa15, power hx2) I'm not going to try and replace it until I can afford one in the $400 range. I can't help but wonder about the audiopipe bd3s performance. When that time comes I will be getting a new alt and another alpine amp to run to whatever sub I get. My highs are good to go. This buy far isn't the best sub out there but it is for a sub within the $200 range.
I have both the TXX APA 15th anniversary editions as well as the TXX BD 3s in my system. As you say for 140.00, what a deal!!!. 3 inch four layer coils on those, so how can you go wrong. One problem with the alpine is the 2.6 coils, at least for the 15's. You can't go wrong with Alpine, but the coils are on the small side, along with true power handling.
The TXX BD 3 outperforms the APA buy a mile, Awesome sounding, down to earth low digging sub. Too bad they just used 3.3 inch coils, but at least they went larger on the coil and 220oz on the mag.
If you can get them for 400.00 each on sale, I am betting the RE Audio XX or XXX 15's would sound real good. They go 8 layer on the coil on those. With subwoofers like that, that weigh in at twice the audiopipes, you got to have a double front baffle or you will ruin your sub.