Cisco are the best. They are machined from solid aluminum and are extremely solid. You can get get a triple cross plate that attaches to a single mounting point that can be removed and installed easily.

I use Scotty rod holders. I worked with a guy who lives in Vancouver and is a charter boat captain there. I had always discounted the Scotty line of products as 'not strong enough' From what he told me, in the Pacific Northwest, a lot of salmon boats use Scotty rod holders. Since I needed to rig an entire boat with aspirations of trolling for Walleye on Lake Erie and salmon on Lake Ontario, I took a chance and went with the Scotty rod holders.

Here is a picture of a Scotty triple holder running a 12 color leadcore in the front holder, a dipsy diver in the middle holder and a stacked downrigger line in the rear position. They may be 'plastic', but from my experience they are durable enough for use in the Great Lakes. Probably would have issues with a large Muskie, but for walleye and salmon fishing, you can get by with this setup. Just keep the drag set at a reasonable tension.
Rod holders?-scottytriple-jpg

You can also mount more than just rod holders. Using Scotty's 'electronics mount', I mounted a RAM iPad mount and repeat the display from my HDS. Can do the same with a FishHawk 4xd.
Rod holders?-scottyipadmount-jpg