Hori does use OMRON for the Microswitches.
I have four HORI Fighting Stick EX2; the Virtua Fighter 5, the Dead or Alive 4, the Soulcalibur IV, the regular EX2.
They have the same Microswitches used in Namco.
Sometimes the Hori Arcade Sticks I listed above do use Matsushita Microswitches though.
Instead of OMRON, sometimes will be Matsushita.
You will sometimes see in the same Joystick BOTH of those Microswitches used at same time.
I had another Virtua Fighter 5 that had OMRON V-15-3A5 and Matsushita AM51630A53N going on.
Matsushita is the company of Miicroswitches that Seimitsu uses for their Joysticks by the way.
But about the Restrictor thing, yes, it does look different.
But just the top is different; extra lines.
Other else is the same; Shaft, Base, Pivot, Microswitch.
The Spring is what I do not know.
I do agree that the feeling is not the same.
But that has to be because of the age or something.
Like the silicone grease being not smooth, or spring being old.
My two Namco Arcade Stick did have old grease which needed replace.
Only thing I can say about the Spring is that in Namco, mine is dark.
In my EX2, they are not dark.
Namco Arcade Stick is made by Hori by the way.
And did you guys know that the Microswitches used in the Namco Buttons are the same brand as Microswitches used in Seimitsu Buttons?
The Microswitches in Namco Buttons are TKC MM9-2.
Same Microswitch is used in Seimitsu Mahjong Buttons, JB-35-T
TKC being Tokai Communication.
Seimitsu use TKC for Buttons.