not vs exists

which queries faster?

not exists:

select productid, productname 
from northwind..products p
where exists (
    name 1 
    northwind..[order details] od 
    where p.productid = od.productid)

or in:

select productid, productname 
from northwind..products p
where p.productid (
    name productid 
    northwind..[order details])

the query execution digest says both same thing. case, permitted form?

this formed northwind database.

[edit]

just found useful article:

i cruise i'll hang exists.