S-F users: any successful sub matings out there?

I own a pair of Guarneri Homage. Depending on what type of music you listen to and how large you room is, you might not need a sub. They go surprisingly low in-room on their own (usable output down to 40 Hz or so). However, adding a sub makes a big improvement, and adding a second sub takes you up to a whole other level. I am sugin a pari of REL Strata III's, chosen because of their sealed box design and speed. They are a VERY good match w/ the Guarneri's, integrating beautifully in all respects. Biggest impac is not so much in the bottom octave (though they will of course do taht), but rather in soundstagin, and midrange/treble "clarity". The second sub was a revelation, really opening up the soundstage.