These shorts are just fun 3 minute episodes to hold fans over until what I assume will be the DxD BorN OVA(s) which may or may not come to be. These shorts are really similar to the ones that aired after the 1st season of DxD.
Not much to review since the specials are so short.
Its just some fan service and comedy. None of the comedy was really all that gut-busting as the specials are more aimed for nut-busting haha (am I right?). Each short involves some sort of provocative situation that Issei finds himself in and thats about it. These aren't anything special but they
are nice to have.
Bottom line is if you liked DxD you'll enjoy these shorts.