WOOX Build your stock

[OldSoup]

I am looking at a WOOX stock. They use the modular approach with their stocks to easily allow for user preferences. I like the Cobra Precision rear, but am wondering if I should go with the forend from their Furiosa. The difference is $20 and the Furiosa has the side M-LOK rails which the standard Cobra does not. Just the bottom M-LOK on the Cobra (both have this)

In the pictures that I see, I don't see many using the side rails on their rifles. $20 won't put me over budget or anything, but is there a reason to have/not have the side M-LOK?

Thanks for your time.