Wilson Sasha 2 Pre owned?


I am now listening to 25 year old Proac Response 3.5 speakers with Audio Research tube electronics.  Great speakers but I'm considering an upgrade.  I really like the Wilson Sabrina but now have a chance to buy pre owned Wilson Sasha 2s in the low 20's. They are about two years old but cosmetically perfect, would include a 3 year warranty from Wilson. Also, there was some kind of resistor upgrade after these speakers were manufactured and the dealer would include the upgrade.  The boxes/crates are not included.  Looking for any advice on whether this seems like a good deal, whether the Sasha 2s would be a big step up from the Proacs and whether the used Sasha2s are a better choice than new Sabrinas (which would cost less).  Have to decide very soon because there are others interested in the Sasha's. Thanks. 
brownsf
Why would you consider Wilson speakers, any Wilson speaker?  Paper drivers in a expensive metal box. There is so much better out there for so much less. I don't know of any other company that laughs so loud on the way to the bank than maybe that other company called air ( spelled incorrectly deliberately ).
  Yes, I have heard wilson's and no I do not like how they sound and I don't care to get into an argument with anyone who likes them because it's just my opinion.
Do tell which resistors were changed , the reason for changing and whether the new resistors are the same as original. 

I have 2 sets of Wilsons. Watt Puppy's and Maxx 2's I enjoy both very much.

Guess I'm just a Wilson "toadie"

I would also suggest listening to other great speakers in the $20k range. I do like Wilson speakers but I like others as good or better, like the usher BE10 or BE20, Revel Salon 2 or Studio 2, Raidho, and many others. Personally, I would buy a used Usher BE10 or Revel Salon2 used before I would buy the Wilson Sasha2. You can get them for 1/2 the price and I think they are better.
I’ve auditioned carefully several times the whole WA range before buying my Alexia and I have no doubt you should skip Sasha 2 and go for the alexia with a little extra budget. You said you’d buy the Sasha 2 in the low 20’s... I bought Alexia for 28k and the price difference is marginal compared to the quality difference. Alexia is just another league (they should cost double or triple the price). They have more details, more bass control, the mid-trebles are more “natural”. Borron an extra 5k bucks and go for the Alexia. I bought them 1 year ago so I suspect 2nd hand price is even cheaper today

p.s. I’ve also compared Alexia with all the magico range, splendor, as well as several other brands. That particular speaker sounds amazing to me and really stands out (better bass control vs spendor, more natural mid-treble compared to Magico)

p.p.s. I drive them with d’agostino momentum stereo