Sorry, got caught up with other things. Hoping to get my review done Monday or Tuesday, might have more ZxV/Slant comparisons. They don't target a super similar sound sig, from what I've found. ZxV is pretty balanced (in terms of neutrality) with some extra sub-bass and a slightly lush, slightly dark response. Closer to the Alpha Dog than the Slants. The Slants, as I hear them, have a fairly noticeable boost in the 100-300Hz region (more of a "woof" sound to everything), and perhaps ever so slightly depressed mids/lower treble relative to upper treble. Slants have a larger soundstage and are a bit smoother sounding, IIRC. Slants do better with channel matching and might be slightly cleaner sounding, though the bass emphasis I mentioned occasionally clouds things relative to the ZxV. Slants are super comfy thanks to the pads and suspension headband. ZxV is comfy too, but the wood cups offer a stiffer construction and fit that required me to bend the headband to get a good fit and seal. Pilot pad is nice, and I do like it, but the suspension headband is perhaps a bit better.
If you're looking at Paradox headphones and want something neutral, just get the regular ol' Paradox. If you want something that's still fairly neutral but a bit on the lush and slightly dark side, with some extra bass below 100Hz, go with the ZxV. If you want more response around 100-300Hz and a larger soundstage, go with the Slants. ZxV and AD have some similarities, but I preferred the ZxV in the end due to its tone and clarity. I guess the AD was more neutral (except the bass) and had a larger soundstage, but it lacked a bit of cohesiveness, clarity, and refinement relative to these others. Had a sort of artificial, hard glare to the sound that I suspect most won't notice or mind. I'd recommend trying both to decide which of those two works best for your ears, though, if considering those two.
I also got a ZMF V1 in from Zach to test. Initial impressions are quite positive. More on that later, perhaps.