A lot depends upon your kayak. If you have a SOT you can buy a seat that has built in rod holders. I reccomend these types of seats to beginners so they can get some on water experience before they commit to drilling holes.
Another consideration is the type of rods you fish with. Most aftermarket rod holders will accomidate spin and conventional outfits but not fly rods. So if you're a fly fisherman you need to get one that will do the job. Scotty makes a specific fly rod holder that will hold any rod. The RAM117 will hold fly rods with a fighting butt. These types of rod holders; RAM, Scotty, Roberts, etc. sit above the kayak. Then there's the type that are mounted in the kayak and a significant hole needs to be cut. they cme in straight and angled designs and each has its appropriate uses.
Another consideration is the type of rods you fish with. Most aftermarket rod holders will accomidate spin and conventional outfits but not fly rods. So if you're a fly fisherman you need to get one that will do the job. Scotty makes a specific fly rod holder that will hold any rod. The RAM117 will hold fly rods with a fighting butt. These types of rod holders; RAM, Scotty, Roberts, etc. sit above the kayak. Then there's the type that are mounted in the kayak and a significant hole needs to be cut. they cme in straight and angled designs and each has its appropriate uses.