I dont know if you heard a properly set-up Quatro but when my dad swapped out the Legacy for the Vandy it was like he had real bass for the first time, he can listen much louder as the Vandy doesnt shout at you and the bass is tight. My dad really liked the Legacy, but found it hard to come to terms of how bad they were compared to the Vandy.
You would think the Legacy bass would dance circles around the Vandersteen with its larger drivers but we both always felt the Legacy started sounding stressed at higher volumes, the bass just got sloppy and the mids and tweeters were very aggresive, they were fed with 300w Classe mono amps so non arguement about quality power.
I would like to see you hear another pair of Quatro only to confirm you must not have heard a well setup pair, with the bass tuning I find it hard to believe you thought they didnt sound good but this hobby is very subjective.
Maybe the new HD trounces the old Focus but I doubt it is a super huge step up, my dad thought he was serveed well by the Legacy and still does.....but the Vandy was just better... also better then Wilson Sophia wich he thought about buying.