To me, and to many others, the MIA is worth the extra cost. Otherwise, no one would buy them. This is a question that only you can answer...
I would *not* characterize the electronics in a Squier CV, Fender MIM or a Fender MIJ as equivalent to a Fender MIA, nor would I say that the build specs, Quality Assurance, or materials are equivalent. To suggest that they are, to me, is ridiculous.
The Squiers are fantastic *for the money*, as are the MIMs and MIJs. So too are the MIAs... They're all worth their street selling price, if you ask me.
It always seems that when this question gets asked and answered here on TB, people come from all directions talking about how their Squier or Mexican Fender blows away every American Fender they've ever played or owned. Seriously, give me a break...
The Fender American Standards are awesome, and so is every other pre-2008 model that I've ever owned or played. I also really like my Squier Vintage Modified fretless, and my Squier Strat, and my Squier Mini Strat, but I recognize they're not in the same league as my MIA P bass.
Sometimes where the quality really becomes noticable is after gigging the instrument for a couple of years. You'll find that some instruments go out of tune more often than others, things break, screws come out and get lost, bridges fail or need constant attention, caps/pots wear out or even break, some necks need constant adjustment, some instruments just don't sound consistent from venue to venue or season to season, etc. You will find that (in general, there are exceptions in both directions for any brand) a MIA Fender is a lot more consistent and reliable in the long run than a MIM or a Squier.
If you want something that will last you 2-3 years before you swap it out and replace it, go for the Squier. If you want something for 5-7 years, get the MIM. If you want something to keep for the next 25-30 years or more, get the MIA.