The type R subs are a great value, one of the best. But if you're wanting great SQ, that's not the direction you should go. Wish I learned of them sooner, but they're marketing in the U.S. is terrible, and the amounts of retailers is just as bad. Hertz, and Audison which are essentially the same since they're owned by the same company in Elettromedia offer a quality I didn't know was available in car audio. The years before I was under the impression JL Audio was the best (excluding the rare extremely high priced items)
I've learned in the last few months that (reasonable prices) JL still makes some of the best amps available. The XD series is very impressive for the cost. The new Slash V3 is overpriced at the moment. Yet the Audison voce line of amps are superior to JL, & the Audison Thesis (no longer made, not reasonably priced due to rarity) is considered by most the best components ever made. The Sax, & Basso are incredible.
I know where there is a 10' Hertz HX250 sub for under 150 shipped, but it's used. Also another 1 that's about the same price. The 1 I'm currently using is amazing. Never heard such a clean, accurate bass near the cost. Don't have an amp at the moment to provide sufficient power but building a enclosure with 2 of the 10's in a dual-opposed configuration. It's the only enclosure design known where the 2 speakers actually work together.
Next level up is the Morel Ultimo 122, & 124. This Sub digs much lower than any I've ever seen in car audio. Most higher end home audio subs can't produce as low as the Ultimo.
Humans can't hear until 20Hz, but we can feel it at 15 Hz. The Morel starts producing at 10 Hz. The guy I got my Hertz HSK 165's from has the Ultimo available for $450, accepts returns and comes with full warranty.
The amount you can save from ordering through someone in Europe is immense. e.g. My HSK 165 would of cost at least $600 through a U.S. seller, I got mine for $325 shipped. Audison I used different seller and haha, still can't believe I got them for under $250 new.
Be surprised if they left this info up, depends on the sites sponsors.
If they do, you won't come close to the SQ of a Ultimo or Hertz based on all I've heard. For under 1k, you won't be able to do better than an Ultimo with a JL 1000 mono. Enough leftover to get a Audio Control, or Clarion EQ. There's another great 1 I'm blanking on the name of
The Audison subs are harder to find. Can only think of one 12' I've seen that's used for $220.
The engineering of the HX is brilliant. Watch the video to see what I mean. His enclosure isn't bad at all, it's just not getting the most from it.
https://www.google.com/url?sa=t&source=web&rct=j&ei=tZHeVOv6Is2eyASUh4KADg&url=http://m.youtube.com/watch%3Fv%3DO6bxRN9BW0s&ved=0CC4QuAIwBQ&usg=AFQjCNF57NI_8ZAp0Pb7hu4IyodcFoSOZA&sig2=n4iU5CwV1Ie2u70A2VL2mQWatch
If you happen to have Hertz retailer in your area, I'd definitely check them out before deciding.
Some other brands I haven't heard outside Morel, but read great things on there components from a few sources i trust that are superior to anything offered by 95% of U.S retailers are the Morel Elate 602 (starts at a unheard of 30 Hz in a 6.5 speaker. Google it and they show 1,200-1,500 cost yet know a Canadian distributor who sold a pair under 400 last week. Also has best passive crossover I've ever seen)
Morel Hybrid, same as above but starts at 50 Hz. Hybrids Audio Legatia, DLS Audio AS6, and Rainbow
Helped me a lot to look at the
EISA Awards 2014-2015 | EISA - The European Imaging and Sound Association award winners over past few years.
Sorry about the novel, but some great information in there that I hope helps