Mezco Batman is anything but 'low-end', but if it's a candidate in this thread, then it gets my vote. Sturdiest 1/12-scale human I've handled, and it represents the comic character very well. I rarely buy doubles/alternate colours of things and I jumped on the black and grey as soon as they restocked, just a few days after toying around with my PX version. The thing combines action-figure durability with genuinely high-end tailoring, paint and sculpt, and it's a crying shame that they aren't producing an armoured Bats to top the the line off.
Revoltech Star Wars stormtrooper is a close second for me. I know some people hate the stylised look and Revoltech joints, but I love the personality you can get out of it with the right posing:
Totally balls-out, ready to wreck some rebels with that heavy blaster.
That's how I like my stormtroopers.