Which one Nikon flash camera is of good quality in these cameras? - 1

Which one Nikon flash camera is of good quality in these cameras http://www.electronicbazaar.com.au/Camera-Flash/Nikon.html

Nikon have a reputation to maintain, as a result they don't make a "bad" flashgun. If you want all the bells and whistles, extensibility and flexibility then you'd probably go for the speelight DX-900 or whatever it's called. But if this is likely to be a one off stand alone item then one of the lower end flashguns is likely to suit better. Or compromise and go mid-range with a model that can work stand-alone for now but that you could use as a wireless slave in the future.

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All of them are good but all of them are different. If you're a DSLR user the SB-700 is the best bet in most cases. An sb-400 can do if money is tight and space is a consideration but it doesn't really allow indirect flashing in portrait orientation and can't act as a wireless flash.

Nikon D3100 is great, not only for you, but also for your non-photographer spouse; my XSi took phenomenal shots, but I had to know how to set it. Can you imagine me going to my non-photographer wife and say, "okay, when you take indoor shots of our kids, set the camera on A mode (Canons expose for ambient light in A mode and adjust flash for fill, that's great), +0.7 exposure compensation, ISO 400 or 800, white balance on cloudy, and shoot." My wife was lost at "okay." Sure the custom modes on the 40D would have helped, but the 40D is old technology; can it take 1080p video? I didn't think so. Plus, what lens are you going to use with the 40D? The 17-55 IS? Great lens, but who wants to spend $1, 000 for a non-weather sealed 17-55 dust collector (google Canon 17-55 and dust)? Will 17-55 be enough for your telephoto shots? Your kids' baseball games? Didn't think so. What about the Canon 18-200? Sub-par quality, noisy, overpriced.