Thanks for the helpful input. I had a day in London on Friday and got a chance to visit the apple shop and a couple of hifi shops around tottenham court road so was able to try out a few phones :
Beats - i cannot understand why these are so popular, overwhelming and bloated bass overloads the presentation making everything seem slightly muffled and frankly not that enjoyable v others i tried. Must be an age thing !
B&O H6 - lovely wide soundstage, good clear presentation and amazingly comfortable. pretty much as good as i hoped they would be but the one area they lacked is what i can only call the upper bass which was a bit light. i thought the deeper bass was there but then there was a lift before a refocus on the amazing midrange which these excel at. great phones and one of the most comfortable but i did eventually prefer ...
B&W P7 - wasnt expecting to try these but i liked these more, they seem to have a more focused bass and vocals, very clear and enticing and for me the best balance across the whole range. closer to my grados than anything else i tried i guess which may be why i liked them. maybe not as compfy as the B&O but if i was sticking to more portable phones i would have got these.
AKG 701 - nice headphones, probably not quite the best style for my taste but well balanced, clean and a nice listen. would be a home use item only but i didnt feel they were grado beaters which i already own.
Beyerdynamic T90 - wow i loved these, detalied, smooth, lovely finish, great comfort. they have the full range from bass to treble all well ordered and instruments identifyable. these were so good i thought they may beat my grado 325e (or at least offer something different). The T90's are so much more comfortable that my grados.
I have now ordered the T90s (at a good price comparable to the others i tried out). I decided home use was the most important and for the train i can live with my cheaper philips downtown for now. I will start by using the T90s alongside the grados, as i feel they are quite differrent. however if i end up always using one over the other i will likely sell one pair off. It will be exciting to start to try out the two side by side but my hunch is to keep both for different times and experiences - the grados are amazingly punchy with the best rhythm of any phones and wonderful basslines. These would be complimented by a smoother and kinder T90's both on the ears and for longer term listening.