The short version
8 companies supply this market — a reasonable cushion if one runs into trouble. The brand price has fallen 51% in a year, to $1.03 per unit — and generics that get this cheap tend to get abandoned rather than defended. Generic versions run $0.8636 per unit — 3.7× cheaper. Put together: this looks like a healthy supply — the boring kind, which is exactly what you want.
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