What will the 558s offer over what I'm listening to already? Anything they'll shine on in particular?

Howdy!   I love my Sony v6s and my Grado sr80s. The Porta-Pros aren't balanced enough for me (too bass heavy). I've considered modding them, and I probably will at some point.   All of my listening will be done at a desktop, with my headphones amplified by a Focusrite 2i4 interface.  ...

The price is what's holding me back from the m50s. If I'm at all satisfied with the v6s, then I'll keep them for a long while. I'd say that I won't buy more headphones, but I think we all know that is near impossible to do, yet so easy to think.   I like neutral sounding phones, and I think...

I'm expecting that I'll probably be a little rough with these headphones if I travel with them much. It would be nice to not have them wear out after a year or two.   The more I read about the v6s and see pictures of people in recording studios with them, the more I really want them. I think...

I've thought about the 440s, but I remember reading that their bass could leaving me wanting some more thump. I still think they'd be nice in terms of their highs and mids, but the bass...   As for the zx700s, I want to be able to use these on the go if I need to, and they don't really fold...

I'm really leaning towards the v6s. They seem to be what I'm looking for right now in this price range. Unfortunately, I can't audition any cans. No audio shops around me, and I can't make an hour and a half drive to listen to some cans 

I've been reading headfi for a few months now as I get more and more interested in headphone listening.   I'm looking to get a pair of closed cans that I'll be using for home use and some travel in cars and maybe busses later on. I have porta-pros, which I really enjoy listening to, but I...