Going to take a pretty hefty terminal strip for that!
Yeah, from the size and length of the blades, I would expect a terminal block/socket designed for them to be something on the order of the sockets used for 240v/30A. Certainly not a JST connector!

For 150 amps you'll need at least AWG #3 wire
No, just pulling 20A @ 48VDC, for which 12ga is fine. The more expensive model does have power factor correction, which is certainly a point in its favor, along with more normal terminals (copper blocks with clamp screws). The blades on the cheaper supply are far longer than needed to attach lugs or even bus-bars, which is why I asked if there's some sort of terminal block or socket that they're intended to slide into.
As far design goes, I've plenty of experience in knowing what decently protected power circuitry looks like. Yes, it needs an outside enclosure, but good internal design doesn't leave large bare conductors in close proximity where a stray fastener, etc, can cause a serious short. Breaker panels have big bus-bars in them, but they're also shielded and the blades on the breakers slide into proper contacts.
Given the amount of metal chips that go flying from a mill in operation, ranging from tiny needles or glitter-like flakes to spaghetti-like chips 3-6" long, you need a good enclosure, filters to keep the crap out, and a design that won't self-destruct if something does get in. Heat-shrink can cover the blades, but if there's some sort of terminal or power distribution block they're intended to slide into, that would be better. The steppers are all well-protected and draw about 5 amps each, and they get fed from a Gecko driver that handles current sensing, speed control, etc.