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The dog-bone shaped ones are cylindrical ceramic caps, which generally do not fail and usually don't need to be replaced. I would generally use a mica capacitor to replace one that failed, although a ceramic cap could be OK. Modern ceramic caps have many variations, and people often don't know much about the differences between them. Some have a lot of drift; others have very wide capacitance tolerance that varies drastically with temperature and applied voltage. Micas as generally very well behaved. Bottom line is that in almost every case a mica cap is OK, whereas ceramic disk caps may or may not be well suited to the particular circuit.
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