Nothing, so long as you add the losses that would be associated with the complete column length when calculating overall "pump" efficiency, that's provided overall efficiency forms part of the pump test acceptance.
It is a capital mistake to theorise before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts. (Sherlock Holmes - A Scandal in Bohemia.)
That's exactly right.
Also make sure the vendor has performed critical speed analysis (this is done on paper) to make sure you won't run into resonant frequency problems with the actual pump at actual job speeds. Also good to double check minimum submergence criteria will be met in actual sump.
