I don't know of a reason more (or less) of one or other might be desirable over the other. If you are just talking a few units either way, I don't think it's worth worrying about. Whatever works for you.
In TLAP you will have read about basal testing. That's the established best way to determine your basal, and once that is done i:cs can be more easily and effectively found. But again, if you have your own methods or different options that achieve your desired level of control, it's all good.