The best stax I've used were these:
Late 70's Music Man 2x10 on top of a late 70's MM 1x15. The 210 spkrs are stock and deteriorated and the 15" spkr is a mid 90's peavey BW @ 4ohms. Both cabs ported. Early 90's GK800 sitting on top in bi-amp mode. Very powerful, loud, and versatile. Awesome tone. In fact the 1x15 alone can keep up with a fridge.
2 Eden d115's, stock speakers, with a GK400 on top. Easy to carry, great tone, very sexy looking.
TC Electronics: RH450 on top of (from top to bottom) 2x10, 2x10, 2x12. VERY LOUD. very clean. My volume was at 10:00 and it still made me nervous. Outside! Always used a mic before but the DI was so good I didn't even bother.
3 Ampeg SVT's stacked with a GK800 pre-amping an old Crown pwr amp lead sled. Damn.
1975 Ampeg Svt head on top of 2 flatback Ampeg 8x10. DAMN!