This is more of an engineering choice. This will really depend on the exact fit you want. Tell your machinist what you want to do and they might have a reccomendation. Hope this helps.
A lot of this depends on the machine house you use to make your parts.
Where I used to work when it came to bearings it depended on the ABEC number it was. (i.e. ABEC1 looser then ABEC7)
The higher the number the tighter the tolerance. We used to use ABEC1.
For a press fit we would do 0.005in. to 0.010in. press
Where I am at right now we do press fits of +/- .0005
As a suggestion I use this website a lot for technical info like what you are looking for.
Also check the Machinery's Handbook.