I've noticed all of the ibanez guitars these days (except for some prestige, S series and the hard tails) use the Edge III.

Is it stable, durable, reliable? I've heard it doesn't have great tuning stablility, but can be fixed with the old chap stick trick.
Quote by Martindecorum
tuning seems fine on my guitar, but there is a little piece that i have heard breaks but is simple and cheap to replace, it break due to the material used to create it

yea ive heard this about all ibanez tremolos, but my dads a metalworker, so i figured i'd be fine with that asepct :P
As long as it's set up properly it stays in tune pretty well until the string get really old. It's a good bridge in terms of stability.
I dont know about durable. I've seen one that split and about a quarter of the baseplate/knife edge came off. That was after 1 year in Eb with 11's. Could have been a defective one from the factory, but still, that shouldnt happen.
They are made of cheap pot metal, so they're a bit soft and much more likely to break than an Original Edge or Lo-Pro, but those last for decades.
It a great trem for what it cost.

Not the best ever, but not the worst.

Mine stays in tune great. As with any guitar, if it is set up correctly it will stay in tune.

I have heard the knife edges wear out but I've had no issues with mine at all after 2 years of abuse.
Jackson RR24M - EMG ALX w/ ABQ installed
Ibanez Xiphos - stock
LTD Alexi 600 - stock
Ibanex RG - Tone Zone(bridge), PAF Pro(neck)
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Fulltone OCD
MXR 10 Band EQ