I use flashers and downriggers quite a bit for salmon on downriggers. I'll use the same gear (minus the bumper) for both lead and downrigger fishing. Moving away from downriggers for salmon has become trendy and I think people are taking a very valuable tool out of their toolbox (more accurate depths, less drop on turns, better in tight quarters, ability to use lighter rods, more enjoyable hookups (the wife will refuse fish on lead rods, etc.). Honestly I find that salmon really aren't too concerned with them as I'll fish one of my favorite river spots 8' down on the rigger with a 15' setback in 12-13 FOW. At times salmon prefer lead rods and at other times they prefer downriggers and when I can I'll use both techniques simultaneously.
In a river setting I have my setbacks between 15-20' (sometimes down to 10' and up to 25') how far my setbacks are depends on how much traffic there is around me or how tightly I have to turn. When my fishing spot is busy I'll shorten them up and when it's empty I'll lengthen them out.
In an open ocean setting I may go a bit further back just because there's more room to maneuver and less traffic. In these settings I'll typically go with 20-30' setbacks.

 

The 360 flashers will spin huge circles on long setbacks. The short bumper length provides that “pivot” point from which you can control the diameter they swing out. Triangle flashers act the same irregardless.

 

My go-to flasher on riggers is a large LEO. Hands. Down.

RW

 

The 360 flashers are just the latest version of old-school dodgers, and they were originally developed ocean and Puget Sound salmon fishing behind downriggers. They give a lot of "thump" and vibration as they work, and as they swing side to side they give action to otherwise unmoving lures (hoochies, cable rigged herring). For that side to side action to work, you need a short leader of a very stiff material (super short actually gives more wild presentation, the longer you go the more moderate the dancing around is). I go very short for coho (18-24"), and longer for chinook (24-32" or so). They create a ton of drag, and a downrigger is the only effective way to get them down really deep (50+ feet), but you can fish them shallow for coho behind lead or a diver. They work in the river to (as witnessed by their new popularity).

The inline flashers (triangle flashers) came later, and are designed to create some flash and vibration while being low drag, so you can use them in rivers w/ strong currents like the Columbia and Willamette, and in places with strong tides, without having to run giant weights and big meat stick rods. In the last 20 years or so, they have been the most common flasher for people who mostly fish the rivers and Buoy 10, so when the new marketing of 360 flashers as the hot new thing came out a lot of folks were unfamiliar with them. They work well for their intended purpose, and you can certainly also use them in the ocean behind a downrigger to create some flash and vibration, they just don't add any action on their own. If you are running herring, spoons, plastic superbaits, etc... they work great behind downriggers

There are a few, like the LEO's and the old Kone Zones, that you can change the leader attachment point on and create at least a little bit of eccentric wobble action.

Some of the old Les Davis and Luhr Jenson dodgers from the 50's and 60's are pretty collectible now.

 

The Pro Troll Pro Chip was the original 360 flasher(has the fin), it was designed to give spoons and hoochies action when trolled slowly , so you could also fish bait at the same time. We were using them in the salt in the 90's. The Pro Troll Hot Chip is the standard skate board flasher...........

I have caught lots of kings down to 100" with an 8" Pro Chip and Ace Hi Fly 12" to 18" leader trolling 3+ mph just above and behind a Kone Zone daisy chain.

For deeper I prefer my Qcoves.

We have always tied our flashers directly to our main line. This is what makes the Qcove break aways my go to, they will slide up your line after you hook a fish. Orange Crush rules..........

I have caught kings and coho on non 360 skate boards at b10 with 16oz, they act like a large dodger and swing side to side..

 

You just gave me a great or terrible idea for Kokanee fishing… attach the dow****** clip to the 360. And the 360 to the ball with like 24in bumper. Run like a 10ft set back on the clip. Or what ever gives my stuff good action.

 

You just gave me a great or terrible idea for Kokanee fishing… attach the dow** clip to the 360. And the 360 to the ball with like 24in bumper. Run like a 10ft set back on the clip. Or what ever gives my stuff good action.

It's called a false flasher/dummy flasher. I have wires 6' to 10' long. I have 4" protrolls for kok's, not sure how they wld respond to a 8' or 11" flasher.

I tried a pink 4" pro troll with a small pink ace hifly for coho once, they ignored it, like I insulted their dignity.....

 

All I use is pro trolls in chrome anymore but I used to use the other brand behind riggers and did well. The one with out the fin. I want to say Gibbs?