A small point but IMO needed is that a barrel roll and an aileron roll are 2 vastly different manuevers:

In aviation, the barrel roll maneuver includes a constant variation of attitude in all three axes, and at the midpoint (top) of the roll, the aircraft is flying inverted, with the nose pointing at a 90-degree angle ("sideways") to the general path of flight. The term "barrel roll" is frequently used, incorrectly, to refer to any roll by an airplane (see aileron roll), or to a helical roll in which the nose remains pointed generally along the flight path. In fact, the barrel roll is a specific and difficult maneuver; a combination of a roll and a loop.

Barrel rolling is not used in aerobatic competition. Both the Boeing 707 and Concorde prototypes were barrel rolled during testing. The 707 was rolled just once by Tex Johnston while Concorde was rolled multiple times by her test pilots, including Jean Franchi and Brian Walpole.

I trained in both while learning aerobatic full scale flying but the barrel roll is NOT used in competition. This is stated above also. A good barrel roll IS much harder to execute than a simple aileron roll.