I actually agree with last two Snap Circuits assessments above, and think ColinsMum's idea is on the money as to the reason. In addition, Snap Circuits are definitely a stand-alone item, so may not be a good choice for the OP. But still think they're a neat toy, and that they might be of more than passing interest for a child just starting to think about electricity moving in circuits, etc., and the first time that child hooked up something and saw a light flash or a spinner spin, it might be a memorable experience. Would they hold a child's interest for a year, or even many months? Maybe not.
I still have a soft spot for the toy Capsela too, even though it also might not hold the interest of a mechanically inclined HG+ kid for very long. For what it is, a neat toy that encourages a child to think modularly for what may be the first time when very young, it's not bad IMHO.
