It's not unless you want to use ie800 specifically with sony/hifiman daps.I would advise to buy an armature iem with detachable cables for ZX2 or later if you get hit by the upgrade bug uncommon as it may be if you decide to stick around this site and decide to go for WMIA/Z,the new sony flagship than practicallly rendering your ie800 useless with any other gear.Frankly i would advise if you are sort of money and can't afford to buy a new flagship iem to sell ZX2 and go for QP1R,much better synergy(ZX2 and ie800 are too warm and can't utilize to full potential without changing cable),supreme detail,clarity and soundstage with no need to rewire cables,from my 20min demo at a store i can see this as endgame for portable use,easily.
I am partial to ie800,it has too unique and memorable a signature to use just with one dap,it's like a chameleon and can be very satisfying with the right gear which ZX2 is not.