The 93 is the Mack Daddy of the Pioneer Tuner DNA legacy and don't let anybody tell you any different. There was some backlash because somebody (a literal "mac daddy") of U.S. Tuner design fame declined to work on it and that became the basis for the "it's complex and therefore to be avoided" fables that thereafter ensued.
Here's my capsule review. (I'm working on one for the Tuna group, but I don't know if I'll ever get it put up or not.....)
Some buttons ARE not necessary or particularly beneficial. The fake Stereo application was meant to compete with the old C-Quam AM Stereo movement of the '80's and it's pleasant but NOT Stereo, so it's a fail by design. Not bad if you like to "play with stuff" (Sonic Holography, etc.) but not "Stereo" either.
The Stereophile "damned by faint praise" review disparagingly said it resembled a VCR in programming complexity. Anybody who's lived with a Microsoft operating system (then or now) will think this machine's utterly simple to use.
Even its detractors said it's the RF hottest tuner (very possibly) ever built.
The sound is, if anything BIGGER/more dynamic at the frequency extremes than the F-91. (I've owned multiples of every tuner since the TX-9500 II with the single exception of the F-26.) I don't DISLIKE the 91, but it's lack of user accessible controls (particularly with regard to IF bandwidth) makes it very much "not my cup of tea".
I've owned two F-28's and they sound more like the 93 (and 91) than any other Pioneer Tuner I've ever aligned/owned/restored. However, they're not my "cup of tea" either because they can't be purposefully "detuned" in order to assist in IF bandwidth narrow DX'ing. The 93 can be microtuned at 10khz increments in "Fine Tune' mode.
I'll be selling off a bunch of my extra Pioneer's in the coming year. I will keep one TX-9500 II, one TX-9800, one 91 and EVERY 93. The rest (including the 449 and F-90) are going to auction. YMMV, but if you like the Pioneer "house sound" there's not an awful lot to be offended by if considering any of their other models. But to me, in every aspect of performance, the 93 was their last "statement" piece and there's precious little "wrong" with it. I own three. They all are uniformly excellent......