True, the two-burner style is more stable, especially important if using large, heavy pots (e.g., purifying water in large stock pots). It's probably the best choice for home-only use.

I prefer the one-burner just because it's handy: I won't hesitate to throw it in the back of the car "just in case," and I could schlep it into a base camp for group cooking (not everyone is comfortable with a white gas stove).