Knownothing, a few things I can add:
Micro walshes were the first "series 3" model released I believe and all micro walshes are series 3. As I understand it from John Strohbeen, Ohm owner and principal Walsh series designer, the difference between series 2 and 3 is in the tweeter only, so I would expect much of the overall presentation to be very similar between series 2 and 3.
Series 1, which would include original Walsh 2s, 4s and 5s from th 80's, are an older Walsh design and I can clearly assert much inferior in regards to imaging accuracy and overall timbre.
If the 4's were rebuilt in the 90's, I suspect there is a good chance they are series 2. Your friend would probably know for sure what the difference was when they were rebuilt.
Regarding, cables, I hear huge differences with different interconnects from my digital sources using the Ohms or my Dynaudio Contour 1.3 monitors, perhaps even to larger extent with the Ohms since they are more full range, but I have not done sufficient experimentation with speaker wires to say much about that.
I suspect the differences with speaker wire is less significant in that I am using premium Audioquest cv-6 wires to my Dynaudios but all other speakers , including both pair of Ohm Walsh are in different rooms from my electronics and hook up through rather industrial grade in-wall wiring. The Ohms have such a large soundstage and image so well, in their own special way, that I do not notice any adverse effects despite the big $$$ cost in the wires feeding them.
Also, amplification makes a huge difference with Ohms, more so with my larger Ohm 5's than my 2's. You need high current and significant damping factor for audiophile results at most volumes with the 5's. The 2's are not as fussy those these things still help. The micros are smaller than the 2's and I suspect even less sensitive to current and damping factor specifications accordingly.
Your description of the Walsh speakers imaging and sound stage signature is fairly accurate. The effects of studio or concert hall acoustics on recordings are what they are. The Ohms will reproduce this more so than other speakers perhaps. They will also present this in a manner that depends more so on the signature of the room they are playing in and this will change based on speaker location.
To me, the imaging characteristics of the Ohms are what make them special and exciting. They actually capture the sound of the original recording environment and translate it accurately into your room. The trick is to realize this fact and not resist it and use it to your advantage when setting things up and listening.
Short of listening back in the original environment recorded in (impossible), what more could one ask for? As a long time Ohm affectionado for this reason mainly, it is very hard for me to stay interested for long periods of listening to most any other system I hear, save those perhaps which cost tens of thousands of dollars more.
