From your list the Monolith THX Select is the top choice, IMO. Followed by the PB-1000. Best bet is to wait a while until Labor Day, which will spawn some sales. The Monolith has been as low as $375 and the PB-1000 is usually around $400 in the SVS outlet during their holiday sales. Both of these subs offer 20Hz performance with a linear sound. The Monolith can even be operated sealed. The other subs on your list are mostly budget subs and none of them offer much performance below 30Hz. With a $400 budget, best move is to steer clear of the budget subs.
Subs>RBH I-12e, I-12. HSU VTF-15H mk2. Monolith THX 12(x2)/THX 10(x2). XTZ 1X12. SVS PB-1000(x2). Speakers>JBL Studio 270/235c/230/225c, Arena 130/125c. Sony CS3/CS8/CS5. QA 3020i/3090Ci, 2020i/2000c. Monolith Cinema 5bs. Polk RTiA1/CSiA4. Other Audio>Sony MDR-Z7m2, XB900n, MDR-V6, XB700, XB32, XB31, XB22. Sennheiser HD58X, HD4.50, PC37X. SIVGA SV004. HyperX Cloud PS4. TB Stealth300. LG FH6, RK8, RK7, PK5, PH4. HK Onyx Studio4(x2).