I feel compelled to chime in as, I too, have to agree with Texas42 and Demosis. For the record, I have been a Magnepan user for over 20-years, having owned models from MMG to MG-IIIA, to include a pair of 1.6's which I based my comparison of the 1.7's on.
The 1.7's I listened to were being driven by a NAD integrated amp and CD player, with Nordost cabling. The speakers were completely broken in.
I'll be very brief; I did not like this loudspeaker. For that matter, I did not like the 1.6's either, finding the voicing of both speakers to err too much in the direction of the upper registers, thus imparting a cool, rather than neutral or warm, tone.
Granted, both speakers do all the things that Maggies do very well, so I am not quibbling about their performance; I just did not care for their tone. Anyone who has ever owned a pair of MG-IIIA's knows exactly what I am talking about.
Are they a worthy successor to the 1.6's? Only time will tell. As with all Magnepan's they will have their following. Whether or not you like them will have to be determined by a thorough audition.
Personally, I feel that Magnepan should have re-released the MG-2.7QR, as for about the same price as the 1.7's, it was simply in another league. JMHO.
WPM