There's always preference and taste, and there's nothing wrong with preferring Stax. They're well regarded for a reason.
However, to say you have attempted some number of mods and then make a generalization that Stax is always better is not supportable. There are dozens of mods and even very minor changes can have a huge effect on overall sound with a given configuration, and the mods have a huge variety of sound (and accuracy).
Compared to your mod, whatever it may have been, your statement is of course valid, you have a preference. However, compared to ALL mods, and for all music and tastes?
Of course there is preference. Your post is great example of the pot calling the kettle black. You have not heard my modified fostex or my SR5 yet you tell me "it's not supportable" to for me to say the STAX has better sound quality. I can tell you with 100 percent certainty I have heard both . The fostex driver has slower settling time that smears inner detail and dynamics. My ARTA measurements and ears are not lying. The "mods" do nothing to the driver. The fostex driver is not capable of resolving to the level of the electrostatic membrane. Even my electret Signet TK33's have superior sound and resolution over the fostex driver. As far as preference I can think of other dynamic drivers/phones I'd take over the fostex without hesitation and for less money and no mod needed.
Edited by Magnetar - 6/26/12 at 3:19pm