I have the Shure SRH840 and the Audio Technica M40x, I bought these Fostex because I wasn't happy with the Audio Technica M40x due to their lack of definition in the lower middle range, on the other hand the SRH840 are good in all frequencies without any muffled mids or over the top bass, they sound really well.
To my surprise these Fostex T40RP are able to be even worse than the Audio Technica, because they lack clarity in the entire middle range and not just at the bottom of it, is just something that I don't get it, I remember those days were headphones were competent doing this at less than 40 euros, and nowadays they aren't at more than 160 euros, one feels like asking for rocket science, and on top of that comes the usual expression "good for the money" as the new way to make this stuff acceptable. The real problem is that many brands like Fostex just pump up that bass and sell it as good to people that don't know better.
Concerning comfort they are also the worst of the three, with the Shure SRH840 being the best ones, again. These are most painful if you let them be too much on the up side position, but even when lowered they retain some level of discomfort.
Given the build quality, they look good and durable, but that tiny orange cable, I wouldn't really care about it if the sound was good, but it adds up, the cable is very short and with the same lockable L shaped on both ends, why? Am I supposed to connect two Fostex to each other directly? Must be rocket science indeed.