I suppose I should be grateful to the IE800 for getting me interested in higher-end headphones. I found a second-hand pair for a good price and was curious enough to try them. They're extremely detailed and also have very impressive bass – not boomy, very articulate. Also quite a wide soundstage. I also realized I had to swap my FiiO amp for something a bit higher-end, as the IE800 revealed noise from its audio circuit. In any case, I was extremely impressed, hearing tonnes of things I'd never heard before, and soon decided to invest in some proper open-back headphones and other equipment for listening at home.
The thing is, the IE800 is just awful if you're on the move. The seal is totally inadequate, and it's impossible to get third-party tips if the factory ones don't suffice. If I'm walking around listening, I'd rather have the IE80 with Copmly tips, which has a great seal for me – I can actually hear more that way. So the IE800 was effectively only useful to me for home listening – but was rendered superflous by HD600, 800, etc., that I'd gone out to buy.
Even worse, the thing is awfully built. The cable is too short, the headphones are soldered to it, etc etc. I'm already having problems with the cable – scratch/loss of signal – and I know that I won't be able to replace it because the drivers aren't detachable.
Given the asking price, I honestly can't recommend this, however good it can be under certain conditions. They need to sort out the cable, make the headphones detachable, and provide options for getting a better seal. If you're obsessive about high-quality audio on the move, you may as well pay for a custom IEM. If not, you're probably better sticking to open-backed headphones and listening at home.