This is a difficult query, because response times vary based on many parameters !
Among them are:
The number of data fields could be anything from a few to several hundred.
The server load will obviously be heavier just after market close.
There is also a dependency on the data template. For instance a Time Series extraction is slower.
For these reasons it is impossible to give a meaningful number, but just to give you a feeling, do not expect a response in a few seconds, this will take some minutes ...
Here is one test result we can give you: for an End of Day extraction, with 10 fields, 1000 instruments, we measured a time of 22 ms per instrument.