money is really the question. i have the sb400, 800, and 2 900's. they are all great. sb400 is awesome for what i think it was meant for. it has far more power than your built in flash, and will save your camera battery and make that last longer since it doesn't have to power the flash. i use energizer lithiums in it and it seems like they last forever. you can do bounce flash while shooting horizontal with it also. great flash!!! if you've got more money you might look at a SB700. it's a newer flash and i've heard great things bout it. i think you're lookingat about $369. way more power and will do more. i have a D40x that my daughter is now using and that's a neat little camera.