Before buying my 20's I had been very content with my westone es5 customs for many years (eq'd, not the stock sound). I had basically resigned to not getting anything else unless something really got my attention. When i heard about the isines they were the first thing that had intrigued me in all those years, especially since i had owned lcd2's at the same time as my es5's for a period of time, and decided I was much more content with portable headphones than large cans even though i loved the lcd2's
Since the price was not rediculous, and they had the 30 day return policy, i decided i'd give the 20's a shot. I had also realized that for me, having an open portable would be more ideal in most scenarios than my very isolating customs.
I also knew that I would very likely not want to give up using my clip zip unamped as my primary listening device, so I would either have to be content with the analogue cable sound, which is never the case for me with any headphones, or be able to eq them to essentially sound as good or better than my customs. I figured that was a lot to ask for considering my customs were $1000 and I was very happy with them.
It took me a while to get the isines eq'd to my liking, and I almost returned them, but once i got them sounding good, I was very happy with them. I am a bit unique to other listeners as I have worked with eq my whole life in various sound situations, and in my own way I feel I have a very good handle on "optimal" sound for headphones, so to me the "stock sound" of a headphone is not so much relevant. It's all about how good I can get them to sound. How close to my idea of what a perfect headphone should sound like can i make them.
Bottom line, i was amazed. To me with my eq settings they sound really really good, and as far as I'm concerned I'm back to where i was with the customs, which means I'll be hanging on to these for a very long time unless something totally mind blowing, and relatively similar in price comes along.
I've had my 20's for a while now. My customs have been collecting dust. I will keep them, as there is always a place for isolation, and at this point they are outdated and have little resale value, but I have found that I had to completely re-eq them to get them to sound as good as the 20's, which has not been easy.