Interesting review. I could certainly quibble about placement, but he seemed to not have other options. Also, the point of measuring outdoors, what is in effect a quasi-omni-directional design, seems questionable. I do admire and respect the reviewers efforts, if not all his conclusions.
I had a pair of Series IV 901’s in the 70’s. In 2009 I bought a pair of Series VI’s, which I still have, and use in my main two-channel rig. Yes, the 901 is not a perfect design and I would never claim such. But boy, oh boy can they deliver the raw power and scale of live music into a room! I think that considering all the trade-offs and compromises inherent in loudspeaker design, most of us "weight" distinct parameters of sound reproduction differently. If dynamics, scale and space are high on your list, it’s hard to beat the 901’s for the money. True, there’s nothing like them (for better and worse), but man are they a lot of fun to crank! I listened to my remaster copy of Van Halen’s first album this morning. I have the 901’s on 26" stands, 15" out from a short wall in a 15 x 22 x 9 room, and crossed over at 80 Hz to a pair of Velodyne 12" subs sitting in the corners behind the speakers. Cranked up, not to "11", but to around 95dB peaks, the sound is awesome. Visceral and enveloping, just like live music. They may be relics from a bygone era (so am I) but I still love’em.