Yup, the full ATX support in the PC-V700 is why I'm so big on it. Like I said at the time, it isn't perfect, but it's a pseudo hybrid which fixes most of the issues with the PC-V600, PC-V354, and the various left/right A05 iterations.
One of the best things about the PC-V750? It'll take dual socket boards, of different "standards." Even the SR-2/SR-X will fit, but you're looking at a bit of the right side of the SR-X hanging beyond the mobo plate. Other dual sockets are a cleaner fit. Very nice high-end air/moderate water workstation build candidate.
Deciding between the two for different prospective builds. Maybe both? Maybe neither? Well, it's better than international shipping fees.
Sucks that Lian Li is still monetizing anodized interiors. They make it difficult to find "Xs." Instead, you have to go with the windowed "WX" variant, and pay extra for a clean panel, separately. Pricing doesn't much matter, these are both going to be big sellers for them.
edit: Just noticed you also mentioned potentially getting both. Of course. BTW, V700 could use a little bit more room behind the mobo, but at least slim 240s should clear most motherboard/ram combos, with at least a pair of fans. All internal.