I don't own either but have a question.
If time is not an issue (time would favor using the Domino), what are you going to do with dowels that can't be done some other way. I use cauls to keep boards flat when doing a panel glue-up, and regular mortise and tenon joints. Both are fairly simple, easy, and low cost.
But I only do furniture and not cabinets (like kitchen cabinets) so maybe there's applications I'm not thinking of. I've never encountered a situation where I wished I had a dowel jig.
Mike
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