I usually use a stored procedure to add new rows to my tables. I have in some cases passed the new ID (PK) as a parameter to the SP and in other cases allowed the SP to generate an ID (PK) all by itself and then return the ID back to the app. I know this is a case of "six of one and half a dozen of the other" (or as we say around thse parts "a-horse-a-piece"), but I have decided to choose one method over the other for my future development.
Any thoughts about which method is better. I am currently leaning towards passing the ID as a parameter to the SP because I think this might be slightly faster.

What do you prefer? Do you use SPs exclusively for this (insert, update)?

Einar