I don't know about "best," but a good floorstander speaker I have heard that meets your criteria brand new is the Tyler Acoustics Freedom F-3 at $1450/pr. (gets down to 35hz)... A couple used floorstanders are the Sonus Faber Grand Piano Home (this one is going to be tough to find for $1500/pr. used, but well worth it if you do) and Opera Audio Eric-3s (usually can be found in the $1200/pr. area used).
---Dave
---Dave