I started out with FALs before switching to the M1A. The FAL is probably the most ergonomic battle rifle, and is a classic example of 1940s technology and 1950s manufacturing. The receiver is not trivial to manufacture, particularly when compared to the M16/AR-15.
I've built a number of FALs on a variety of receivers, and while you can WECSOG them, there are things to be aware of. The best kits i can recall were the early STG58s, which had little more than rack wear, and barrel that looked like they had hardly been used. The German G1 kits were also pretty nice. The later stuff got worse and worse, and more expensive.
After running through several FN, I started to get frustrated with the horrible triggers and poor accuracy. Folks have been accurizing the M14 since day one, and making one shoot MOA is pretty well understood and a number of smiths can build a nice rifle for you. It's easier to scope a FAL, but at a certain point it hardly seems worth putting on anything more than a unity optic or dot.
I'll put my Kreiger barreled M1A with it's 2.5 pound Rader trigger against any FAL made on the 600 yard line.
That being said, I plan on getting another 'Congo' length FAL.