Surprisingly, it fitted fairly well on my keyboard tray - which is almost the same size as a Kinesis Advantage. Okay, the keyboard was overhanging a little bit, but the stand of the board is a bit smaller than the top, so no problems there.
When the keyboard shifts position - you notice. It's not like a beep or a message box that you could train yourself to ignore, trust me, when your keyboard moves under your hands you notice. This could be a good time for a screen break.
The keyboard runs through 4 different positions. At each change, the keyboard swaps to a positive or negative tilt (relative to the surface of the desk). I prefer the negative tilt myself - but I believe that change may be a good thing. The two halves of the keyboard expand out for several steps and then contract together for several steps (and don't forget that the tilt changes at each step). You can lock the board into position, or trigger the next step at will.
I few people have complained that it's noisy, but if you're in a open plan office, it's not all that bad once you take air conditioning, printers, etc into account.
So far, so good, but there are a few things I feel could be improved.
The cursor keys follow the line of the other keys on the right side. Smartfish have done a great job making the board look nice and have really made the cursor keys/number pad flow nicely. It's not comfortable, sadly. Dropping the numpad would help and I hope they'll rotate the cursor keys clockwise. Oh, and I really miss home and end.
Some of the keys felt stiff, this might be due to the fact that I bought the board on ebay, but then the keys don't look all that shiny.
Overall, it's pretty good. (Don't get me wrong - I'll still be recommending the Kinesis Advantage.) It's easy to adapt to (it doesn't look intimidating) and it will change the positions of your hands/wrists during the day.
6/10
The board hasn't been available on smartfishes's website for a while now...
I'll add some real photos soon.