AI's are great rifles, no doubt. A system that is truly greater than the sum of it's parts.
That said, it's a "one size fits most" system. It's the suit you buy off the rack. It may fit you perfectly, if you're lucky. But most likely the sleeve pitch is slightly off, perhaps the shoulder pads hang off the shoulders a bit much, the collar is a little loose around the neck, it "X's"/bunches up slightly when you do up the top button. But it fits, mostly.
A custom made rifle is like a suit tailored specifically to you - caveat is that you must have a great tailor (i.e. gunsmith), and you need to know exactly how you want your suit to fit (your rifle spec's). It took 3 iterations to get my custom rifle to where I would call "perfect". I've been around a lot of AI's, great rifles no doubt, but I would take my custom rifle in it's current configuration over an AI 10 times out of 10. My rifle is built exactly the way I like it, and I wouldn't change a thing about it. With an AI, you are pretty much stuck with how it is, for better or worse.
The rhetoric that an AI is much more reliable was very true ~5-10 years ago. My first custom rifle, a GAP Crusader was pretty unreliable when compared to an AI. Well built modern custom rifles are much more reliable than they were a few years ago. The quality of custom rifle products has increased dramatically over the years. Well built custom rifles aren't any more unreliable than AI's these days, regardless of what empty rhetoric you hear often repeated on the internet. I've seen more than a handful fo AI's go down in matches, and custom rifles aren't going down near as much as they used to.
AI is a great choice, especially if they fit you. A custom rifle may be an even better choice - but there are a few caveats attached to that.
I'm never going to replace my customs with an AI, as my custom rifles are a superior rifle for me.
