Snaq: if word flow is defined as the little "is this your next word in this sentence?" suggestions, then sure. Never used that much. The only thing that makes Swiftkey > Swype for me is the fact that random buttonmashing in the general area of what Im aiming for will get me crazy results. Not the suggestions it makes.
Swype does the same, sure, but its a force of habit to get used to one after having used the other for a good while.
Oh, and obviously none of this is onehanded, since... you dont type fast onehanded compared to twohanded on a device the size of a smartphone these days.