Hi
What does everybody think between St.Croix 5s66lf2 and the 5s66mlf2 for 18-24 in. rainbows. Is the light action to light.Customer will be drift fishing mostly many different baits. He had me do one and he wanted a stiff rod and I used the ms66mf2 which is to stiff not enough feel. Other brands won't do he wants St. Croix.

Mike,
I feel your pain.
I have gone through the identical situation with a couple of customers.

Finally, I just built up all three of the rods. i.e. the medium, medium - light, and light rods.

Then, I let the customer fish with all three.

As it turned out, the customer ended up buying all three. When doing this sort of fishing, each of these rods are suitable for different situations on the same drift. So he is well pleased.

But if he were to choose one that he used about 80% of the time, it is the medium light for drift fishing.

The light is a touch light for much of his style fishing, and the medium is a touch heavy for much of his fishing.

P.s.
It is also somewhat dependent on the type and weight of the fish that he is catching. The medium light and medium rod will handle any likely fish on the drift, but there might be some issues with the light action rod.

Of course, as is the case with any rod. You can catch virtually any size fish on virtually any size rod. If the rod is too light for the fish, then, simply keep the rod pointed straight at the fish, and effectively hand land the fish; rather than rod land the fish.
i.e. use your elbow to land the fish, while keeping the rod unbent and pointed straight at the fish.

I use this technique all of the time if I happened to be using a noodle rod to catch pan fish, and happened to get bit by a 10 lb northern. As long as the line doesn't break, you can point the rod directly toward the fish and just hand land the fish.

Take care
Roger

Try looking at the Lamiglass G1000 freshwater series.

I've been using one for 35 years.