Summary: I bought this same desktop configuration for my office at work a few months ago. I have used Microsoft's ergonomic keyboard (4000) before I made this purchase and really liked the layout.
I was looking for an ergomic mouse due to developing pain in my right wrist and I also wanted a wireless split keyboard. The keyboard is nearly identical to Microsofts wired ergomic keyboard (4000) without a couple of indicators (caps lock and number lock) on the keyboard itself. The mouse is really comfortable to use and keeps your wrist in a more natural position. It did not take much time to get used to its' different shape. The SW selection for the mouse is also nice. My only gripe is an occassional signal issue that I have but this is very infrequent.
I liked this combo so much that I just ordered the same set for my home PC. I would highly recommend this setup if you are looking for something that has a good ergonomic design.

Summary: Earlier this year I started using a KVM so I had to give up my Bluetooth keyboard/mouse which has worked flawlessly for a couple of years. I found a really good deal on a Microsoft \"Wireless Laser Desktop 6000\" so I went ahead and purchased a couple since I've always had good luck with MS keyboards and mice in the past. Even though I got a good price, that turned out to be a horrible purchase because the wireless receiver was so bad. If you are a touch typist, you should avoid that set at all cost unless you enjoy constantly having to retype whatever you were working on (I'm a programmer, so it was extremely irritating).

After about 3 months, I finally gave up completely on that set and decided to go shopping again. This time I did a little more research and bought the Microsoft \"Natural Ergonomic Desktop 7000\". This is a review of the new set, which is MUCH better than the previous experience I had - I am going to try to review the keyboard, mouse and receiver separately even though they come in a single package.

*** Keyboard ***
Pros: I've been a fan of the split keyboards ever since I started using one almost 10 years ago so that isn't a problem for me at all. I also like that this keyboard has the normal layout for the insert, delete, arrow and other special keys between the keyboard and keypad. Since I tend to use keyboard shortcuts a lot, it really kills me when those special keys are laid out differently to save space. This keyboard also has a zoom key right in the middle of the keyboard and I've found that it is actually fairly useful when configured as a scroll button instead of zoom.

Cons: I really don't like the function lock feature that seems to have become a standard feature on the new MS keyboards, but I can live with it since it doesn't ever switch out of the F-Lock mode unless you manually push the button (which I will never do). The other problem is that the space bar makes a horribly loud clicking noise when pressed - almost like it is getting stuck on the way down. I have read that other people have noticed the same thing and if I were working in an office that would probably be a deal-breaker for me since it is sooooo loud. Since I work from home, I figure I can deal with it.

*** Mouse ***
Not a whole lot to say here since this mouse works exactly as expected. It is a more ergonomic shape than I was previously used to, but it hasn't turned out to be a problem at all. One thing I've notice with both the 6000 and 7000 desktop mice is that the scroll wheel doesn't work everywhere that it should. That's kind of a weird problem since my previous MS mouse worked everywhere. Anyway, that's not a huge deal for me since I don't use it much - but my wife had to get used to it in some of the programs she uses. (I'm not saying that the scroll wheel doesn't work at all - just that there are a few things it doesn't work in where it should.)

*** Wireless Receiver ***
The wireless receiver is much better than the type that comes with the other non-Bluetooth MS keyboards and mice. It is about the size of a USB flash key and plugs directly into a USB port. The reception is very good and seems to work just as well as any Bluetooth receiver I have used. It's also nice not to have that big mouse-sized dongle sitting on my desktop - which always irritated me since I'm using a wireless keyboard/mouse exactly because I want to avoid wires on my desktop. I did have a problem plugging it into the USB port on my monitor since it was a tiny bit too bulky, but I worked around that by using a little male-female USB extension key (for ~$2) and just plugged the receiver into that. I've been using this desktop set for about a week now with not a single missed key.

*** Conclusion ***
Overall, I'm very happy with this purchase - although it was a bit expensive. If it weren't for the irritating space bar, this would probably be a perfect setup.

As one last comment, I should say that if you're not using a KVM you really should at least look at the Bluetooth keyboard/mouse combos from Microsoft. Those have excellent range, never miss keys and don't have the irritating space bar from this set.

Summary: The keyboard does its job well for the most part, but the wireless range was pretty bad. Don't plan on using it more than 3 or 4 feet (yeah, seriously) away from the receiver.