Morgan, I have no experience of the HD-495's but I do have 3 sets of Sennheiser 'phones. My first pair were bought about 10 years ago, and still in use today as my 'cooking' headphones. They are HD-480 Classic, and cost about 40/50 UKP. I get the impression that the 495's are the current top of the range in that 400 series. I would think that they would be a very good general purpose 'phone. I also notice that they have a one point fixing on one side only, for the cable. I think that is a step in the right direction, as my only beef about Sennheiser's is their 2 pin connector in each earpiece, gives nothing but trouble, but I still think their headphones are superb! However, I got serious about headphone listening, and some 5 or so years ago, I bought the HD-565 Ovation 'phones. They cost about 120 UKP, and served me well untill I splashed out last Autumn and bought the HD-600's. Now they really are GOOD !!!
Check out HeadRoom at
http://www.headphone.com/layout.php for everything you are likely to want to know about headphones, and there is an excellent review of the HD-600's on the Stereophile web site. I use them via a Musical Fidelity X-Can V2, by the way.
Hope that may be of some use, and remember, the HD-600's will cost you, but at least you wont be ripped off in the US like we are here in the UK !!