The selction of Adil Rashid will naturally provide great excitement. A potentially very handy legger and continually developing batsman, that is an exciting prospect. However, like Richard says, it's one to approach with caution. I personally would be happy for him to build a compelling case in County cricket, 'A' team tours, etc, before handing him a start in a Test match.
What he may bring to the England side in the future is of such importance that it is not worth risking any damage to his development. However, people in the know will be aware the kind of person Rashid is, whether he truly believes himself that he should be playing Test cricket and whether any negative performances will have a long-term effect.
Crucially for me, it comes down to whether his inclusion in Test cricket at this stage in his career is going to speed up his development, enhance his experience in a positive way, and importantly strengthen the England side. All things for the management to weigh up.