I am agressivly saving up to buy a DSLR. I want to stick with nikon, so I have narrowed my choices down to D50/D70 and D100. For those of you who have each, what are the pros and cons, as far as memory cards, cost and all of the otehr variables. I am more then likely going to be getting it off of ebay, and I have found different combos/sets that are from $500 - $850 ranging from the D50 to D100. Thaughts? Insights?