Mike Rigby-Jones says:

Depend on whether accuracy or cost is important to you. Resonators are cheaper and more robust, but less accurate than crystals. Resonators are available with built in load capacitors which is handy. If you are going to be doing any particularly critical stuff such as high speed async comms then I'd go for a crystal, otherwise a resonator is fine.

see also

• http://www.murata.co.jp/search/ic-e.html . You put in the chip you're using and it tells you which resonator to use.

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