For you use, either camera would do.
You may have trouble finding the Casio EX-S20U.
The Amazon site says it is discontinued and they suggested the EX-S3. Which cost quite a bit more than the EX-S20U.
....
I am a professional cyclist and I have been looking at the Casio Exilim EX-S20U, and the Minolta Dimage Xt. Although their performance is not excellent, I am willing to accept this in return for small size and weight so that I can carry this in my jersey pocket.
Are there any other cameras that I should consider?

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