I bought a DGT in early November, just before GT 5 was released. I used it for about three weeks and generally liked it. I came across the Fanatec Porsche 911 GT2 wheel, however, and I realized that it was what I really wanted. Although the DGT is a good wheel, the GT2 is a whole different ballgame. The force feedback is much smoother and stronger, the wheel works on Xbox 360, PS3 and PC (DGT only works on PS3 and PC, but not Xbox 360) and the alcantra leather on the GT2 feels much more authentic than the plastic DGT wheel.
My view today is that if you play racing games on your Xbox 360, PS3 and PC, then the only real option is the GT2.
All of that being said, you made a good choice. The DGT is a good wheel. You just might find yourself yearning for more at some point. I did.