Ok, it has been well over a month now since getting the used D200 and I promised I would post my thoughts on this camera after moving up from the D40. So, first and foremost is picture quality. Is the D200 that much better than the D40? In some instances... I would say yes.
I had noticed that many of my images had much less noise than previously when taking with the D40 when closely examined in Adobe Photoshop Lightroom. Nope... it wasn't due to better glass. I was using the same lenses with the D200 as I did with the D40. I would say it was in part due to lower ISO numbers and better interpolation of the data with the electronics. The D40 is limited to 200 as lowest ISO rating while the D200 will drop down to 100 which is what I tend to use the most.
In fact, I find it hilarious that some, like photo guru Ken Rockwell, think the D40 is better because it defaults to ISO 200 as if ISO 100 is just to low to consider usable. Ken IMHO is example of why you should take info from the net with a grain of salt. Smart guy that makes sense sometimes and other times he makes you wonder what they heck he was thinking. Personally, if you look at all the gear he reviews, I feel he just doesn't spend enough time with any of it to really develop a good evaluation and seems like he is quick to judge things.
Another thing I noticed when zoomed into my photos, there's was less chromatic aberration than previous with the D40. I normally had to play around a little with this more in Lightroom until I checked out the highlight areas of my D200 pics. Its not to say the problem disappeared but it was noticeably less an issue than previous shots taken on the D40.
I love the viewfinder of the D200. The smaller viewfinder of the D40 seems like child play in comparison. This has really made the D200 more enjoyable to use. Its like looking at a big HD screen in comparison to the D40.
The AF system on the D200 rocks too. I love having more control over the focus because I often shoot subjects off center.
I got the MB-D200 dual battery grip with this camera. While it does add extra weight and size to the camera... I really don't mind it and like the added battery power and additional controls for vertical portraits.
I am really getting used to the bracketing mode which is great if creating HDR images. I do wish I could automate this process just a bit more but still handy as it allows me to set a bracket order and increments up to 1ev then just snap the multiple exposures in sequence. Its too bad that I can't step up or down more than 1ev each bracketed frame though. However, should I desire a 2ev step... I can just bracket for more frames and delete the middle ones that I don't need.
One day I hope Nikon develops a camera with more remote control options and automation built-in. For instance, wouldn't it be great if you had a little remote that had LCD and could show the camera's menu remotely and allow changes in ISO, WB, Shutter, AF, Aperture, etc all from the remote so you never had to touch the camera through a series of shots? I realize some of this possible when tethering a laptop but... I would prefer to just have a small hand-held remote than carrying one more piece of heavy and expensive gear on a hike.
I am really glad I made the jump to the D200 overall and glad I didn't just opt for the D60. I feel I have more room to grow with this camera and it should serve me fine for next couple of years at least. I am sure after a couple of years I will be looking to upgrade to a used version of the D300 though for the added ISO range.