I recently bought the 685 S2 and have been very impressed with the sound quality.
Some reviews claim they are forward and bright sounding-I don't find this the case.
I feel they are a revealing speaker with a smooth and uncoloured sound lacking in any "boxy resonance".
Being front ported also makes them flexible regarding placement-I have mine on wall brackets.
Yes there are probably better speakers but these are currently being run out at US $500 which makes them an absolute bargain and a definite best buy.
I am running them with a 100w Rotel power amp and while perfectly adequate I feel they would benefit from better amplification.
I own the 685 S1s. Bought a used pair last year for a bit over $400. I can say that I don't find these bright at all. If anything I find the bass sort of" boomy". I suspect that this has to do with my amplifier pairing. I have an old NAD 3150 50wpc amp that I bought here on AK. At times the pairing is elegant, but I like a sharp, distinct bass in most music. Will be experiment to find the best combo. Not sure if wiring matters much for this.