I go for the "middle" size. Pink Lady / Delta Diver are simple and effective. I use Deep-Six also, you have to make sure the "trip" is adjusted and you have to re-set (in your hand) it after it trips. The others will re-set just by giving 'em a moment of slack. I have some funky magnetic ones (inheirited) I don't trust and haven't used.
We like to run deltas on the forward rods and deep 6 in the back to get a bit more separation since the deltas dive so much harder than the Deep sixes. That will put the Deep Sixes further back behind the boat at the same depth.
My prefernce is a Deep Six since you can trip them and get them back to the boat a bit quicker, helps if you are piloting the boat.
Jet Divers would create a mess down there, one they don't dive as hard and when you cut the motor to fight a fish unattended lines will float up, and that could easily be under somebody elses boat
Ordered up some Fish Seeker divers from Cabelas on a friend's recommendation. They are really easy to adjust for depth, and seem to be a color that the fish go for. If you look in the catalog, they are in the section with the downriggers instead of where the divers are listed. The pink ones seem to catch the most fish.