Well, the grip part is right.
It has nothing to do with an N frame.
The L was made by making selected parts of the K frame and barrel larger to withstand the modern practice of shooting .357 in large quantity and hot loads. The K frame barrel where it screws into the frame is smaller than the L; same with the frame there. Also the L cylinder is larger than the K, but smaller than the N.
Cracks me up when people post "Why doesn't Smith make a K frame in .40--I'd buy one!" Just not enough metal there.
Don't need to have the rounded crown; the L's shoot just fine. The L-frame barrel shape is supposed to resemble a Colt Python and they are square-ended too at the muzzle like the snake-gun.
L's lack the aesthetics of some of the others. Purdy is as purdy does, in this case.