My two cents.
I build, from a blank, a few Southern guns a year; and I always shape the upper forearm in the "V" shape. I think it goes well with the general architecture of a Southern rifle, and it gives the forearm a very slimming look.
Here are a couple of pictures of my gun. The lighting makes it able to see the upper forearm pretty well. You can see that it is flat, and you can see how that accentuates the curve at the top of the forearm; a feature I also like.
Food for thought. And I'm not opinionated at all.