I have used the old-style Scotty rod holder on my pram for years and have never had any trouble whatsoever...when I actually use it. There have been times when I was lazy and didn't put the fly rod into the holder and paid the price.
However the Scotty base system does not bolt to our raft/pontoon frames very well and for this reason, we have used Folbe brand for a number of years as it bolts tightly to our frames. Good company and based local out of Seattle but they can be a little "sticky" at times and I have preferred the Scotty holders for quickly getting the rods in and out of the holder itself.
Just today I received a new holder from Stealth products and excitedly bolted it to our frame and it fits very snugly. Other features I liked about it are the durability, compactness, and lightweight. I am looking forward to using it while fishing as soon as the opportunity arrives. I think these will be a good fit for kayaks, pontoons/rafts, and even boats with sliding rail systems. I will be doing a product review on our Facebook page after trying it out in the field. I can envision mounting two holders on my boat, heading out to a spot with the 2-rod endorsement and backtrolling the heck out of some plugs.

So far, I am impressed with Stealth holders. Another benefit is the base looks to be adaptable with the Scotty holders if you already have one.
One-Motion Release Rod Holders. Keeps your gear secure by gripping the rod handle. Just pull up to set the hook.
www.stealthrodholders.com