The first problem I seem to see at the moment, is that there appears to be, in effect, no automatic belt tensioner. The belt is tensioned manually with the screw and nut. To fit a new belt you'd need to slacken the manual tensioner all the way, then fit the belt, and adjust up the screw and nut again. Then you'd have to keep watch on the belt tension, adusting it as necessary. This is the system that cars used back when they had V belts driving their accessories, before serpentine belts with automatic tensioners were adopted. It can work, it's just an extra maintenance item.

The second problem I believe I see at the moment, is there does not seem to be any way to stop the reel when the engine is running. I would regard that as dangerous. There may be a clutch in the engine output shaft, but if so it is concealed by the safety cover in the picture above.