I confess i should have checked the specifics, i had wanted some larger or what i would consider regular sized maracas, but after some amusement at seeing this shrunken pair i got around to trying them out and was quite pleasantly surprised.
The sound has good a edge and presence for such small maracas (obviously lesser than full sized tho ) and the contents are well controllable, perhaps only larger 'swishes' are less effective because of the smaller surface to roll around.
If you haven't played maracas or you only require their minimal use now and again this could be a good place to start. They are acceptable for studio use - miced and recorded, probably not good live, but if there is a place in your music for maracas then their should be space in your music for maracas, so if there's not a stack of marshals to compete with onstage you may be able to get away with playing them in front of the mic .
So i would say the sound is good for what it is , it is only slightly limited because of it's size.
The quality is good - wooden handles and skin but bound and not riveted. When they are well shaken i can see some fine particles / dust exiting from the heads - hopefully this does not mean they are disintegrating - I wouldn't have thought so tho. On the whole well made, good sound, small but very usable.