MIJ guitars are fantastic. But since we are comparing to a new MIM are you maybe talking about the new Player Strats? Because those are awesome guitars. And I would take one over a used MIJ.
There's sort of a mystique around MIJ that I don't understand, personally. A ton of guys get them and immediately redo the electronics as they're said to be subpar. Just get the MIM, I have 4 MIM Fenders and they're all great guits.
The one MIJ Fender (ST54) I had, made in 2014 (bought new), came with ceramic pickups, mini pots and a plastic thing that maybe could have been called 'a switch'. But for the rest, it was a quality crafted guitar. Very nice 'V' neck I remember.
I would definitely play them first. Japanese Strats have a great reputation, but the only on I played sounded like doo-doo. Player Strats look and sound good, but they're common. If the MIJ outshines it, get that one.
My first professional grade electric guitar was a MIJ E Series 1980s Fender Stratocaster. I played that thing for about 10 years and the neck was so thin it gave me cramps. Ironically I sold it to help fund another MIJ guitar, a Gretsch Duo Jet. The new Players Series Strats are basically taking the place of the previous MIA Standards. If I could not play them first I would go for the MIM Players Series on instinct.
It's sort of amazing to me how "Made in Japan" when I was a kid was code for "POS", but at some point in the late 70s/early 80s when American pride seemed to be at a low ebb all of a sudden MIJ was almost supernaturally celebrated and in awe as the creme de la creme. I think that both statuses attributed to stuff made in Japan were overblown...
MIM / SSS For no other reason than, that is what I would choose, and have chosen three times. 2012, '14, & '15....and I love all three. MIJ Strats are pretty hard to come by in the States, so they're typically over-priced for what you seem to get (mostly just bragging rights to other Americans that don't have one in their collection). I've had opportunity to play two in my lifetime, and didn't ever impress me enough to compare to the MIM Strats that we have an abundance of.
We are of the same mind. I've had several MIJ which were all good, most on a Par with US models. I've owned two MIM, a while ago mind, and I fell out of love very quickly. I wouldn't touch one now. My current and long standing Tele is Japanese and can hold her own against any US model, let alone MIM. Just my opinion mind........
I'd need to play them both first to make a choice. If I couldn't play them first, I'd go with the "new" MIM Player you mentioned. MIM Fenders are great guitars. The good news is that unless you get a bad apple, you can't go wrong with either one.
I've owed several MIM and MIJ Strats. You can't go wrong with either. Buy whichever feels best to you.
My MIM is like a piece of fine wood furniture. I have never held a MIJ. I have held the $5k Eric Clapton, it feels identical to my MIM, to me. With better electronics.
The only japanese fender I had from 2015 as I'm a JV collector was this one: Amazing guitar and I kinda regret selling it. Never tried mexican fender but if as many of you say that it's better than japanese, I'd say bull**** but everything's possible