A sensory toy is useful only if it fits the task, setting and type of input you are seeking. Someone working through a report may need a quiet object for restless hands, while someone decompressing after work may want stronger pressure or a more absorbing activity.
Start with the situation rather than the appearance of the product.
Ask whether the item must stay below a video camera, fit in a pocket, work beside other people or occupy your hands for an extended period. Noise, resistance, texture, size and cleaning needs will affect daily use far more than novelty.