Some advice on D600 and lenses.

Hi

I have upgraded from a D200 to a D600 and am loving the image quality.  However, I have 2 DX lenses.  I thought I would just live with them as I've spent up on the D600.  One - which was my favourite lens - is the Nikon 17-55 f2.8.  The other is the Sigma 10-20 f4-5.6.

I've pretty much already made the decision to sell the 10-20 as I didn't use it that often and have a Sigma 17-35 f2.8-4 which can take it's place.

However, I am finding it frustrating to see the full frame in the view finder with the 17-55 and am thinking of selling it to fund a walk about lens.

What would you do - would you keep it because of it's quality and live with the DX limitations?  Or would you sell it and if so - given I can only spend what I get for the two lenses - what would you buy?

Nuala