One of my data processing steps is to apply a function to a field that updates the field contents to standardized values. I can accomplish this using either the Calculate Field tool or use an update cursor. The latter is roughly 5 seconds faster (12 vs 17 seconds) on a table with 142k records.
Is there a best practice or rule of thumb when deciding which approach to use? What are the advantages or disadvantages of either case in this situation? I also wonder if the Calculate Field tool is running an update cursor sort of behind the scenes.