Definately go with the two burner break apart. The burners on the 4 burner one are too close together to get anything but small cookwear on. If your cooking for a big group, the four burner turns into a two burner anyways as the big pans won't fit side by side.
What I did was buy their new extra wide two burner stove (22") with built in wind screen. Partner Steel Camping Equipment
I then I bought the two burner break apart to boot along with a single hose and regulator so I can run just one burner if I want. I join the two at the bottle with a Y if I run them both at once. This gives me the option of setting up the kitchen for 1 to 4 burners. It's a great system for a big group or small, and I'll never have to buy another stove again.
A friend on the last Deso trip was so impressed with the two burner break apart, that he is going to sell his 4 burner and get two of the break aparts for the very reason that you can put four big pots and pans on them for big groups.