Best headphone with enough soundstage
I am looking for a great sounding budget open headphone with an outstanding soundstage. Of course I hate sibilant highs and boomy lows. Rather I care clear bass guitar notes and pronounced mid (for female vocals specially). The question is - should I go for HD6XX or wait for HE4XX? Or, anything else?
Of course I am not an audiophile. But I'm gradually appreciating better quality of music. I don't have very good amp (only FiiO Q1 MK II (portable)). Among good headphones, I already have OPPO PM3 that I really like and my MD+ is on the way and I am waiting with huge excitement. Among mediocre IEM, I own 1More Triple, F9 PRO, Primo8, and UM PRO 10 (new), and among headphones, WH-1000XM2 and Momentum 2.0. So, now I would like to have the taste of open sound.
A question for MD people - if I do not buy HD6XX now, is there any possibility that I could get a drop few months later or next year?