Absolutely. The Fostex is like a Denon 2000 on steroids. It has a gorgeous sound that is really satisfying musically.
What put me off before I got mine were the reports from people saying things like hifi 'purists' might not like it because of the bass. I had a feeling it might be really fat. I was wrong. It's not fat but hits hard and fast. The bass is lovely and my own preference as far as headphones go since I don't like a sound that is too etched with a thin bass.
Also, reports of recessed mids. Again, it's not as recessed as I was led to believe. Perhaps recessed is a bit strong and it needs another descriptor like slightly less in the mids? I don't find that a problem either. In fact, I'm not really aware of it.
If anything, I find that the treble can feel quite strong but it has a pleasant quality. It does show poor rips with ease though. The Fostex is very revealing of the source.
I use the Denon d2000 sitting at home with portable devices and a D600 with a short lead for the garden.
For sheer luxury listening, the Fostex th900 is a hard one to better for real musical enjoyment.
Btw, the 3d plots above only go down to 200 hZ. The big difference (apart from that treble peak on the ps1000) is way below into the sub bass. The th900 keeps going at very low frequencies where the PS1000 really doesn't. I really like the Golden Ears site. No messing around, just hard evidence!!
For me, that's the main reason why I didn't get one. Rock doesn't have that solid floor of the th900. Although the th900 has a bass hump, you're not over aware of it with the depth of the sub bass.
In fact, even the HD650 doesn't go that low as loud as the th900. I have had a filter on my Senn hd650 to raise the sub bass and since it went home (I had it on loan) I've found the Senn lacking in real deep bass. I'd say that a th900 as it is has better bass than the Senn as it is. With filter, the Senn steps up.
I was a little wobbly about the price of the th900, but once I heard it, I felt that I had really got a headphone that at last suited me enormously.