get the Sophia's it won't have the hot tweeter setup of the 5.1's. Bass response will probably be the same since the 5.1's were not full range, and the mid-bass improvement will be stunning on the Sophia's. Plus you could end up reconing the 5.1's because of age..and that's not cheap.
I have listened to the 5.x, 6, and 7 series and only after spending considerable amount of time with the Sophia's did I go with Wilson (but ended up going with the WP7's because I am a acoustic bass freak...) My friend owns Sophia's powered by an ARC 50watt tube integrated and it is truely an amazing and definitely more forgiving speaker than the 5.x or the 7's.
Make sure you do a search for the Wilson voicing technique to setup the speakers as 1/4" can be difference between good and amazing!
Chris
I have listened to the 5.x, 6, and 7 series and only after spending considerable amount of time with the Sophia's did I go with Wilson (but ended up going with the WP7's because I am a acoustic bass freak...) My friend owns Sophia's powered by an ARC 50watt tube integrated and it is truely an amazing and definitely more forgiving speaker than the 5.x or the 7's.
Make sure you do a search for the Wilson voicing technique to setup the speakers as 1/4" can be difference between good and amazing!
Chris