+1 bdp24. Same here I used Infinity servos for a long time. Rythmik is on top of the servo game. There is a little bit of a supply issue as of late but, well worth the wait or step up or down in your plate amp choice.. The best I've ever found. NO they don't work with other subs at all, defeats the whole purpose of using servos. One or the other not both. It's like using a fixed port with a passive radiator one or the other. Conventional subs with correction or not, just a different animal, Swarm, DBA I don't care it's different than a GR or Rythmik servo system.
You can DBA GRs no problem, they been doing that for 6 year at least. Doubles, Triples or Quad towers. Milti-placement to smooth the bass. Pretty amazing actually. Not cheap and it does take a little work just to get to primer.. Well worth it for the best of the best.
No I don't sell or make money from their stuff.. Sure like it though..:-)