My advice and experience may be different from the others -

I don't use decoys much, but when I do (mainly when hunting with my son or early season when the turkeys are bunched up and strutting in fields) I use several of them. In the early season I may use the B-mobile strutter with several hens. Later I take out B-mobile and just use the hens. I've never had much success using a jake decoy.

I believe that using several decoys takes a turkey's attention off just one. The longer he focuses on just one decoy the more likely he is able to tell it isn't real. That's my hypothesis anyway. It looks more realistic in my opinion, and I have had good success with this tactic

In my area when I see turkeys in fields there are typically several of them, rarely just one or two (until much later in the season).