I've never gotten the complaint about it being rough on the forearm. Do people really dig their arms into the sides of their basses that firmly?.
Absolutely, yes.
I had a Ric that I played all summer in 1976, and the edge of the body formed sore red "slash" across my forearm, hurt to the point that I started wearing an athletic wrist sweatband around my forearm to try to "pad" that area a bit. Still hurt. I had remnants of the red mark for the rest of the year!
Never again.