I picked up a Japanese Squier with an SQ prefix, which makes it 83-84. It was a big headstock Strat style, which gave me the big-headstock jones I still have today. The frets were about worn out so I swapped out the neck for a WD Music Products CBS style neck, rosewood. The only quibble I had with it was that it was made in Fort Myers, Fla., and I live in New Mexico, so the neck warped side ways a little, bowing toward the treble side, although it stayed flat, so the high E string gets closer to the edge in spots. That's what happens when you change the relative humidity from 70 percent to about 30 percent at best. But a good neck overall, fairly thick with good tone.
The basic tone of the Squier was good but not great. Swapped out the pickups for Van Zandt Blues with the Torres Engineering middle boost switch. Now it has serious Strat tone - very clanky lows, shimmering highs and the mid boost for manly authority. Easily nabs Stevie Ray sounds. Also put in a Schaller roller tremelo which gave it some nice singing overtones. It already came with a triangular Mitsubishi auto brass plate epoxied under the bridge (a la Steve Vai, I think), so that gave me the cheap excuse to get creative with it. But I wasn't finished. Gave it a four-bolt plate, took the three-bolt plate (that was inscribed "Waco Wallace" by a previous owner) and screwed it onto the front with sheet metal screws (looks cool) and had an artist friend (Mar Heifner) paint colorful snakes, lizards and a war pony on the black top (with auto paint), plus a flamingo on the headstock. Few months back I added my name on the headstock in Ransom Note font decals that you press on with an orange stick. Not unattractive in a mutant kinda way. Also has a Sharpie signature on the headstock back by Smokin' Joe Kubek, who broke out in a big smile when he saw it.
So there's really not much of the Squier left, but being as it was a three bolt, CBS head Strat, it wasn't as if it were as collectible as a JV-prefix reissue, which are starting to get expensive. This mutant is the best sounding of all my Strats, including a Fender Hendrix Tribute Strat, and four Tokai Silver Stars (which are better than Fender Japan, in my opinion). Currently saddled with a handmade black leather strap with conchos for a fake desperado look, although it also looks sharp with a Planet Waves purple lizard motif strap.
Dan Torres likes early, noncollectable Japan Squier Strats for his pickup mods, which gave me the inspiration, I suppose. I also discovered I am addicted to CBS-era headstocks. I think they give a Strat a bit more beef. Torres' midboost mods are genius in my book - not cheap, but lots of usable sounds. Squiers are good platforms to get crazy on. It sure has been fun customizing it. And it ain't for sale. So make your own! 8)
So in answer to your question, Sinsonido, early to mid-80s Japanese Squier Strats are very good, as good as or better than USA Fender products made then, but the Tokais are better than Fender Japan overall, IMHO.