"No one on this thread has really addressed this question. The move to the much more expensive D3 is more than my hobby retirement based budget can stand. I'm sure the D3 would solve my problem and I would love the camera but I don't want to spend the money".
I addressed it somewhere in this thread - I shoot a D2Xs and regularly print at 30 x 40 with very good results - granted very careful upsizing is required but it is not a problem. It really all comes down to viewing distance...sitting on my couch 10' away, I cant tell the difference between a 13 x 19 from a 22mp Digital Back or a 10mp D200...If you look at the print from 6" of course you will see a difference. I would bet with very good technique and a good upsizing/sharpening process you could get stellar results from the D2H...The D2Xs will easily get great results at the print size you are seeking. And as far sharpness of a print goes the same as a D3/D3S or maybe even a D4 if all shooting settings and technique is equal (Base ISO of course !)