I'm sure my carb could be tuned better, but it's working fine for me. It's a little rich at idle but I have chassis dyno sheets somewhere that show that my AFR is acceptable throughout the whole pull. This is stock out of the box.
On a related note, I had a Edelbrock 600 on the worn out 340 that was in my car before the 408. Never did anything but set the idle mixture on it for seven years. When we pulled the engine, we pulled a plug just for giggles. The plugs looked so good, my buddy said "Save those for your new engine!"
My point is, these carbs can and do function well straight out of the box for someone who doesn't like to constantly tune and tweek their carbs. Am I leaving a couple of horsepower on the table? Probably, but that is okay with me. I haven't touched my engine in two years since it was installed and that's the way I like it.