bench example from the https://github.com/greiman/SdFat project which provided the following result:
Use a freshly formatted SD for best performance.
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FreeStack: 249752
Type is FAT32
Card size: 15.93 GB (GB = 1E9 bytes)
Manufacturer ID: 0X3
OEM ID: SD
Product: SC16G
Version: 8.0
Serial number: 0X24DD08
Manufacturing date: 3/2013
FILE_SIZE_MB = 5
BUF_SIZE = 512 bytes
Starting write test, please wait.
write speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
1017.71,38100,487,502
1004.62,59659,487,509
Starting read test, please wait.
read speed and latency
speed,max,min,avg
KB/Sec,usec,usec,usec
1057.31,492,481,483
1057.31,502,481,483
Done
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