I have never assembled my own sub. However I did own an older velodyne 12 inch sub. I just swapped out my Yamaha rs 700 With a surround pioneer vsx 832 and I have to say with the mcacc setup it sounds a lot better. Very well rounded not too much bass. I'm running 4 pioneer sp bs22-lr and the pioneer center speaker. The system sounds as good if not better than the 1000$ Yamaha unit I was running 6 or 7 years ago I had polk tsi 500s and tsi 200 as rears. I was recommended the pioneer speakers on this forum and love them. I believe they are the best thing for the money.
Also I used to run a psw 10 by polk. It was awful. The psw 505 is way better than the psw 10 in my opinion. The velodyne I had got bad critic reviews due to the cabinet. Customer reviews were great though.
Yeah, the 505 tends to be much better liked than the PSW10. Polk just isn't a subwoofer oriented company, though. Velodyne made some very good subs (and a few cheap ones) and these days their efforts are more pointed towards different areas of technology (automated cars/lidar IIRC). The AJ Pioneer speakers are good value.
Assembling your own sub isn't that hard with a flatpack/driver combo and some glue and a few tools (or you can build your own box), sometimes the quality of the finish is the hardest part
. Follow a design/size box for the particular driver with an appropriate amp and you can get good value, and if you build a second sub for use with the same amp the value really kicks in (altho you have to not charge yourself a high $/hour rate
)...lots of ideas in the diy subforum here.