Can't speak for 4.0.Actually there's no official definition of max cushion shoes, it's up to the manufacturer to decide what range of their shoes would be maximalist. So some less than 40mm heel stack, they classify as max Cushion.
NB 1080 I would considered as their maximalist shoe, but then they release a even more stacked height called Fresh Foam More.
For me , as long more than 35mm can liao, good for short recovery runs. Coz I see the 远征者4.0, older model, cheaper, less than $50 can get. I can't find the spec, so ask around here if they are in the same cat as the NB 1080.. Seems like it is.
I got the 5.0 and don't like it. OK cushioning but poor energy return.
My cushioning rating
Xstep 氢风 - 5/10
Xstep 2000km - 6/10
远征者5.0 - 6.5/10
Novablast 2 - 7.5/10
QD Team2.0 - 7.5/10
Rebel 3 - 8/10
Endorphin Speed 3 - 8/10
Novablast 3 - 8.5/10 (when new)
QD Plaid - 9.5/10
I call the first 3 China shoes my backside itchy hoots. Waste money.
Having said that, i still want to try Anta PG7, even if just for casual walking.
Oh ya, i feel 远征者5.0 is a support shoe instead of full neutral. It guides my running a certain way.
Whenever i run/walk with support shoes, my IT band will flare up almost certainly so that's another reason I don't wear the shoes anymore.
Anyway at 50 bucks, 4.0 is worth a gamble. Can't be worse than Army shoes.