Hans Wegner - CH_445 (Fabric or Leather)  

fabric
I would do it in something like Maharam Pebble wool, which is kind of a grospoint weave but with wool boucle yarns. Think big fluffy bath towel, but in wool. It comes in a bunch of gorgeous neutrals and I think a few muted, rich colors.
I just did an upholstered teak frame chair in the "wenge" colorway, which is a dark brown (as you might guess).
There's also Cato wool and good ol' wool hopsack.
I love leather too but nothing beats wool for color and texture.

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Wegners excellent,timeless work can be oddly "chilly"leather will reinforce this aspect in my opinion.Wool takes dyes well...color adds a real possibility of a "trendy" choice even with neutrals,they are "current".

Bull...
No, wait, Ox.
I know there should be some restraint shown when putting designs together, for fear your space looks like the Vitra Design Museum. But when you bring Wegner into the mix my heart jumps - leaps even, to the Ox Chair in warm brown leather. It is a sumptuous, powerful chair.

In
Agreement...strong agreement!
To me, both are inviting either with fabric or leather. The chillyness could be from a combination of black leather and the chrome base. Even then, there's a warmth you don't see in others like the Barcelona, PK's, LeCorb... I think this stems in large part due to the curves, where the others are boxy and rigid...

Better image
Better image showing some wear & patina. My problem with most images of the ox are they they are in perfectly new, or recently recovered states - which isnt how they'd exist for more than a year or two.
http://flickr.com/photos/matthijs_borghgraef/2502528456/
http://flickr.com/photos/matthijs_borghgraef/2502528456/

Ox > Wing?
I like the ox because its a curious chair. Beautiful in a very unconventional way, but somehow feel more comfortable with the Wing.
Maybe if I sit on it for a few more weeks I'll change my mind.
Am tempted to do the Wing in a Paul Smith stripe fabric (brown base).
I suspect it'd look great in Red leather too.
Does the Ox come in fabric? I have only seen it in leather, and most of the shops I've been to in the UK only offer it in leather.

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Wear looks really great in natural saddle leather...Paul Smith stripe for wing is a very fine choice,his stripes are fantastic...OX in worn saddle leather..wing in stripe.Black leather with chrome reminds me of my shrinks office:)