I cycle between Google/Swiftkey and Thumb Keyboard
If swype+type is your main criteria my opinion is that Google Keyboard is as good as any of the options out there and is progressively getting better every update.
As a long time pro/beta user, I want SwifKey to be my default, but I always end up back with ThumbKeyboard.
It has the best split keyboard layouts and an indispensable row of user mappable keys.
As much as I like the other two, I find I miss the custom keys too much to offset the features of the others
One thing to keep in mind is each one is going to "feel" a bit different (spacing, heat maps etc). Spending a week with a keyboard will tell you more than a quick tryout will ( I speak from experience LOL)
In the end they are all good and in development, so it really just comes down to user preference.