Not cost effective in my opinion. Granted a core as you mentioned would not cost anything in R&D but the cost of producing those clear balls is very high. They are not produced in this country because of the time needed for them to solidify.

Regular bowling balls take seconds for each the core, filler core, and outer core to harden. So in practically an hour an entire bowling ball can be produced. The clear balls take many hours for them to solidify. Plus they would have to be paying the costs to produce them in the production plants instead of using their own.

You can see that in the past, most clear balls did not last too long on the shelves. The Clear Hammer didn't last too long, and that ball had an actual core, as the Hammer in it had dynamics. Even the Widow Clear had hook in it because it had a large round core that rolled up pretty well. But even the Widow clear didnt last that long in relation to the lifespan of a regular bowling ball.
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