Simple question:

Simple question:
What is the best way to loop a dataset?
for u:=0 to Ds.RecordCount-1 do
begin
         Ds.RecNo := u;
         ... do stuff
end;

or

ds.first:
while not ds.eof do
begin
     //stuff
    ds.next;
end;

I use the last one but i've seen tests in wich the first is faster... should it be?