I dont know about you...
For what it's worth, the JS100 does have the coil split and filter, doesn't it? I tried out a 100 a couple of years ago, and the AH1 and AH2 pickups impressed me quite a bit with the variety of tones you can get out of them.
I dunno... maybe it's just me. I used to be a total guitar elitist, where i was *very* picky about every tiny little detail of a guitar in order to even feel i could play it.
Nowadays, it seems i can pick up virtually any guitar and plug it into just about anything and get a useable, pleasing tone out of it. I think it's a combination of me developing a very open mind when it comes to sound and feel, and realizing that 90% of my "sound" really does come out of my fingers.
If you like the JS100, and it works for you, play the hell out of it. If it has serious shortcomings (like poor tuning stability) that get in the way of you really being able to take your music to its fullest potential, then look at replacing it. (or at least replacing the parts that cause you grief)