I think there are no reasons not to use the LMP7708 as a unity gain amplifier. There are no disadvantages connected with the 2nd alternative (feedforward compensation) as mentioned in my former post. In contrast, the other compensation scheme (Fig. 14 in the data sheet) suffers from increased noise properties.
More than that, a unity-gain compensated opamp may exhibit ringing of the step response when used in unity gain configuration. If this is a problem, the feedforward compensation scheme offers the possibility to adjust the loop gain at a value that ensures the best compromize between ringing and short rise time (that depends on the small signal bandwidth).