I had a set of AN/E kits and then went to AN/E HE factory pre-hemp speakers of which I subsequently recently updated their drivers to their hemp counterpart.
The AN/E kit speakers had La wiring originally, front and back birch ply.
I updated the wiring eventually to Lexus for an improvement in detail.
The speakers were very competitive with factory AN/E's and bettered a lot of other audio speakers. My set had a really good 3-dimensional quality to reproducing music and sounded light on their feet. I really enjoyed them. My sense of the factory E's with all-birch ply cab's was that the frequency balance was a bit richer, harmonics were more balanced across the spectrum. I heard another set of AN/E kits that a local speaker builder put together in his all-wood cabinet (and he is what I would consider to be a master builder) and they sounded pretty close to the factory E's-great detail and harmonics. Another set of kit E's I heard were good but didn't perhaps image quite as well as mine-and they had the front and back birch plys.
When I demoed my present AN/E HE factory speakers against my previous Kit speakers there was a huge increase in detail across the board. You are of course talking all wood cabs built to consistently fine tolerances in specific factory assembly conditions, silver voice coils on the drivers and higher matched speaker parts. The increase in detail, smoothness, speed, transparency to different recording materials was blatantly obvious. Thus I kept them.
Updating the silver wired HE drivers in my new speakers to their hemp cone counterparts has taken me to another level in increasing all the musical parameters just listed.
I think you can get close to the factory AN/E's with the Kits, especially if you have good cabinets to house the parts. Vern's kit E's built with birch sounded really close to the factory E's. However, the increased matching of the parts in the factory speakers helps IMHO. The E's have a certain dimensional ability that is quite a balance of qualities.
As for positioning, my E's are on either side of a fireplace hearth that comes out of the wall a few inches from the floor and the walls. So the speakers are not quite in corners but not quite against open walls. I'd say though, hearing the E's in other conditions, that close to open walls and angled in slightly is fine.