Thanks for the responses so far, I'm interested to hear how much the brand and "heritage" of the product my affect YOUR buying habits? Do certain brands sound better to you? Do certain brands have their own style of sound that you like more or do you give every pair of headphones an equal opportunity when buying a set and therefore compleltely ignoring the brand?
I would think it would depend on how one is doing the purchasing. Years ago, I bought a set of headphones that was a brand I had never heard of. Superex or some such thing. I bought them due to how they sounded (and due to my limited budget at the time). For the price I paid, they were superb, much better than anything else I could find at the time. However, if I were buying online instead of at a store, I would go with a brand that I am inclined to trust, because when buying online, one cannot hear them first, so one is obviously not buying them based on how they actually sound, but on revıews, name brand, or some such thing. It is only if one can actually hear them before purchase that one is buying them based on how they sound.
If you have a place where you can actually audition headphones, I recommend going to them and, if you find some you like, buy from them. Otherwise, everything is going to just be sold online, and you will never get to hear and compare before purchase. And that is bad for you, because you will be stuck buying based on other people's opinions (revıews), brand reputation, or some other such thing other than how they actually sound when you stick them on your head.
For me, in a store where I am auditioning headphones, I will try every one that is within my price range, regardless of the brand, and buy whichever one sounds best to me (assuming it seems comfortable as well, because it does not matter how it sounds if you cannot stand to have it on your head for more than two minutes).
In my case in particular, I have not purchased any headphones in a very long time, and listen to music only with speakers. I do not have to worry too much about bothering others, and I prefer not to have headphones on my head if it can be reasonably avoided.