I had a 203/205 in my last rig. As stated they shift really easy, and it's nice being able to just shift the front case to HI for access roads. The down side is you are dealing with 2 heavy cast iron cases, and depending on room, it can be tricky to get the 203 clocked right to clear everything and still be able to hook a shifter up.
For my new rig I used a 246/205 doubler. Shifting is still just as easy. Low/low is 5.4 : 1. It dropped about 30lbs and is a couple of inches shorter that the 203 setup.