I'm in the russ69 camp ALL the way. I like columns.
Second they don't have to be powerful subs. They just need to be well made, if your doing low riders (under 24"tall) a pair of 10" HE reference drivers go a LOG ways too.
I'll give you a "Sonic NUGGET" that is hard to beat. It's my go to driver for 17 hz to 300 hz. 90+ % efficient.
https://www.parts-express.com/Dayton-Audio-RSS265HO-44-10-Reference-HO-DVC-Subwoofer-295-463600-800 watt drivers, they are VERY low distortion 2 is plenty ONE per enclosure. They work well every way I've tried them. Sealed, ported, multi, and passive radiators.. Just a GREAT driver..
You should hear 4 in a column 72" tall tuned with a pair of 12" HE PRs.
I did TWO... 8 CF enclosures. Smooth as silk..
It pressures a room so easy and evenly. I use a 2496 active OX full blown Active DSP with on the fly correction from a laptop.. 300.00 dollars
NOT expensive.. an amp 3-500 for 12K.
What kind of budget is OK? There are 1800-2500.00 DBA kits.. James Romney (sp) and a Guy that is on AG.. nice enough fellow. Answer any questions..