In my opinion which comes from endless hours on the river throwing spinners/spoons. It all depends on how much pressure there has been, what the clarity of the water is, how fast it is and how long the fish have been in the river.

Sometimes a #2 can get slammed all day when no other size could compete and vise virsa with other sizes.

A good one too start with is the #4 .... try it in all silver, silver red, silver green.

Good luck