Superb quality - Geissele Airborne Charging Handle

I don't have any other ambi CHs to compare it to, but it feels more robust and seems better designed than my factory BCM Mod 3.
Knurling/checkering on the arms is nice and grippy but not sharp.
Low profile: Doesn't extend beyond the forward assist/brass deflector, but still ample purchase to manipulate reliably.
As expected from Geissele, it's quality, you get what you pay for.

Only downside I can really say is more of a personal preference. Since it isn't available in FDE but instead in DDC (Desert Dirt Color) it doesn't match the other brown colors I have on my carbine. Not a huge deal, as the mix of FDEs I have don't all match perfectly anyway, but for Geissele to do a proprietary color rather than stick with something that's industry standard is a little disappointing. Not enough to remove a star, of course, since the product is functional and aesthetic always comes second.

If you don't mind perfect color match and want a brown one, go for the DDC. If something like that will bug you, get it in black.
Either way you'll be happy with the performance.