I have no idea what kind of power supply is inside a cheap LED lamp, but if it's flickering, it's only because it's lacking a 20-cent capacitor. There's no reason why it should be expensive to manufacture a 100% flicker-free LED bulb. You could even build your own from parts, for very little money.

Adding a dimmer circuit is another story, because they work by rapidly turning the LED on and off, and varying the time that it's on vs. off.

don't think flicker-free LED lights exist

Well you would be incorrect as a regular single color led like blue, yellow green, and red should not (but can) flicker. There are lots of led bulbs that do not flicker but they either don't produce the correct spectrum, or are great but expensive.

I want to link you to a page with lots of LED bulbs color spectrum. You'll see one that very closely matches an Incandescent bulb.

As for the important factor of flicker, that is not listed.

http://www.designingwithleds.com/light-spectrum-charts-data/

It's not because they're made in the U.S.A., it's because they're made properly. You CAN screw up an incandescent light bulb, and I think all the major manufacturers prove that with each and every bulb they make because they only last what, 1,000 to 2,000 hours whereas Aerotech's last 20,000. You've held these in your hand, you've looked at them up close, so surely you can agree. GE and all the other incandescent manufacturers make extremely low-quality junk. They're out to make a quick buck, and they got the world fooled into thinking that these are the best. Aero-Tech sells a 2-pack of their 20,000-hour incandescent bulbs for around $5.00 at Menards. Most LED lamps last roughly 20,000 and look how much just ONE costs. "Oh, but it pays for itself" Yeah, well what about the low quality of light?

Now, a "good" LED lamp is subjective. What exactly do you mean? I don't think flicker-free LED lights exist, so that's why I'm sticking to incandescent (they have a smooth analog pulsating wave of light). If you mean "equal to these 20,000-hour bulbs", then that might be tough because the reason they're as good as they are is, these are "rough service". It's funny to me how it takes the need for an extremely tough and extremely long-lasting "rough service" lamp to get a lamp like these created. They should be the standard by which all other incandescent lamps are judged.

So, I personally don't know of any high-end or very high-quality LED lamps, but I don't want to find any either unless they can prove with extremely slow-motion video that they don't blink but instead they glow like a steady flame. Until a lighting technology is created that's extremely efficient and low heat that glows like a steady flame, I'll keep using incandescent lighting.