STEPControl_Reader::TransferRoot() slow

Hello everyone.
I use the STEPControl_Reader to load step files in my application, everything works fine, but the STEPControl_Reader::TransferRoot() function is very slow. It takes 34 seconds to run this function on a 4.5 MB Step file. Is this OK? Is there any way how to make this faster?
Thank you for the responses.
CODE:

IFSelect_ReturnStatus status = aReader.ReadFile(aFileName);
if (status != IFSelect_RetDone)
return status;

Standard_Boolean failsonly = Standard_False;
aReader.PrintCheckLoad(failsonly, IFSelect_ItemsByEntity);

Standard_Integer nbr = aReader.NbRootsForTransfer();
aReader.PrintCheckTransfer (failsonly, IFSelect_CountByItem );
for ( Standard_Integer n = 1; n Standard_Boolean ok = aReader.TransferRoot(); //THIS CALL is very slow.
}