Prefer the Seimitsu LS-32 and -40 over the JLF myself. Much easier to use square gates with those than the JLF.
The first time I used an LS-32, it was much easier to play with it off-the-bat than the JLF. The JLF just feels too loose in stock condition. I really needed an extra spring to feel comfortable with it. Even then, I never got used to playing pre-Marvel Vs Capcom 2 games with the JLF. I just couldn’t do dash moves with it to save my life and it doesn’t “feel right” with those games. The current poly fighters are more forgiving with the JLF. Retro and 2-D fighters in general are easier with the LS-32/-40. I consider the -32 and -40 to be better joysticks with games overall. Very good with 4-way gates for Pac-Man; everything else square.
The differences between the LS-32 and -40 are such => the -32 is the bigger brother with not-so-tight feel as the -40 and requires a bit more effort to do moves and manipulate. Still tighter than a JLF, IMHO. It is and isn’t comparable to the JLF. I think more than the spring differences that the gated microswitches on the -32 PCB are the reason it feels better to me.
The -40 is literally a smaller joystick with somewhat tighter tolerances than the -32. (Same springs, though. There is no “LS-40 spring.”) Some people can’t get used to the -40 because of those differences. To play with the -40 really well, you have to be relaxed and use maybe half the muscle that you’d use for the -32. The -40 doesn’t really have the gate bashing problem that the -32 has but with practice you can avoid that on the -32 as well. Both are very well-made joysticks with gated microswitches that make it easier to do 360’s and circular movements on a square gate than the JLF, IMHO. You really don’t have to do spring-mods with the Seimitsu’s. They’re fine stock condition.
My single biggest complaint with the LS-40-01 is that you can’t buy it equipped with an SS Mounting Plate. SS comes standard with the LS-32-01. UNLESS you’re hanging the -40-01 from a custom-modded faceplate, the -40’s flat plate can’t be used with stock Mad Catz TE and HRAP 2/3 SA/SE and V3/VX joystick mounts. Without the SS Mount screwed onto the LS-40-01, it just won’t fit into universal joystick mount areas.
The major advantages of the JLF is that it’s by default the most frequent OEM joystick on mass-produced joystick bases (save some money there unless you wanted a Seimitsu joystick!) and it’s possible to use a replacement optical PCB base with it. A Seimitsu joystick with a FLASH PCB base just wouldn’t be a Seimitsu because you obviously wouldn’t have the gates to nonexistent microswitches!