Just as many people would attack this decision as a reasoned exercise in their various indifference curves and budgets. For others, it could be that the Bling is the Thing.
Personally, I would go with the X31 for ventilation and it would be driven by my cooling strategies. But the Midtower GA-1G8 . . on closer inspection is reasonably well ventilated in the front with a near-certain possibility for double 140mm intake fans. I only looked at the pictures, and Amazon is a notch behind Newegg because the requirements for different resellers in drafting their "specifications" and details doesn't stand up to Egg's practice. I usually look at the pictures first, and again the Egg gallery is less of an effort.
I think I'll just stop here and go look at the Egg's presentation, if they're selling it. . . . OK . . . OK . . . Now I've seen what I like. The GA-1G8 . . -- for aesthetic reasons, has a better bling. It's well-ventilated. You could fit -- almost certainly -- a 240mm radiator in top, and might manage a 280mm in front. Somehow, with those vents, it doesn't matter that you can't vent from the left side-panel, although you could mod the case and the window itself. I'd have to look again -- that can't be tempered glass for an Egg price of maybe $70. If it's Plexi or Lexan, then it departs from the ideal of shielding components. You could fix that with some perf-steel from the local metal-store. In fact, modding the window to fit a carefully-shaped piece of perf-steel is your ticket to adding fans on the bottom end of the case or that window.
Thermaltake has always been the King of Bling. Their cheaper PSUs failed on me maybe 14 years ago; their fans were a bit on the noisy side, but you could control them thermally. They've made some good cases; they've been shooting for the high-end PSU market. Somehow, by the looks of it, the GA-1G8 -- "The Versa C21" -- looks too good for their MSRP or the Egg price.
[LATER] The GA-1G8 is an "SPCC" case, and info so far indicates that to be cold-rolled carbon steel to a Japanese standard or spec. That's a pretty good price for a case like that given its "looks." Would it be quality construction for that $70 price-tag? That's also possible.
I could "do stuff" to that case . . . . . And if it has scars from a botched job, it would only cost me $70.