IE8s, good highs?! No try are way to recessed.
Also for the IE80 to be better than that EX1000 it will have to be one huge improvement, and I mean HUGE.
Also Kaffemman, what of the 3 IEMs have you tried.
I can tell you the EX1000 are true top tier and the IE8 is not. I think you shouted eliminate the Sennheisers altogether and add Westone 4 which from what I have heard is on the same level of EX1000.
The IE8 have smooth gently rolled off treble like the HD650. OP wants "an IEM that has the clarity and balance of the westone 4 but the bass and sound stage of the Sennheisers and from what iv read the IE8/80 and ex1000 are my best options." W4 is the one that should be eliminated given his requirements - bass and soundstage is not a strong point of the W4.
Haven't heard the EX1000 but looking at reviews, the EX1000 may sound better than the IE8/x. The EX1000 is a monitor, therefore I can safely assume that they are detailed and well balanced while still owning the bass and possibly soundstage of the IE8/x. But really price aside, the IE8 is still a top tier IEM and I like them better than the W4.