Duly noted. Unfortunately, you will probably never find the level of sophisticated discussion you're looking for on this forum. The published specifications for each device already tell virtually everything you need to know, yet the ability to reference them in meaningful discussion is like asking people to explain quantum mechanics. Seemingly, the only question ever asked is "how do they sound?" followed by a total absence of even casual comparison samples.
If we just look at a few simple specs (EIN, S/N Ratio, and THD), the answer is incredibly simple. Units like the 70d, M10, etc. perform around -120dBu EIN. This is already pretty good, however units include the SD 7xx series, 6xx series, Mixpre series, the Sony PCM-D100, or the Sonosax/Aeta recorders (just to name a few) are all going to be measurably better. Around -128dBu to -130dBu EIN, and quite frankly, it's never going to get any better than that. All of these units are world class recorders (even when marketed as mixers) and I would challenge anyone here prove even a small difference between something like the 7xx recorders and the "Kashmir" preamps. It's marketing hype, nothing more.
I probably sound grumpy and truth be told I am because how "how do they sound" is a stupid fucking question thrown around constantly on this forum. Feature such as form factor, battery life, redundancy, gain control, reliability, etc. are infinitely more important even when recording mosquito farts. Unless you're putting a transformer in the signal path, these units all "sound" the same (and sound really damn good). No one should be ditching a 7xx recorder for "Kashmir" preamps, especially when the feature set of the 7xx recorders is still significantly more robust.