(see desc) Input Lag #2 - Brook PS3/PS4 to PS2 Super Converter rough test
Short version: no input lag detected with the Super Converter.
Tested DualShock 4 + Brook PS3/PS4 to PS2 Super Converter, vs DualShock 2 in The King of Fighters 2003 on a Japanese PS2, counting the number of input delay frames before Kyo's light punch comes out after pressing the button on the controller.
You can play the video frame by frame by pausing it, then using the "." key to advance, or the "," key to rewind.
0:00 - with DualShock 4 hooked up to Super Converter
0:16 - with DualShock 2
And they come out the same--if anything, the DS4 + Super Converter may even be a tiny hair faster, although not a full frame faster by any means.
Arcade sticks may be a different story. I'd hoped to test my Hori RAP V Hayabusa 2017 with the Super Converter, but it doesn't work. : | [Update: it works now! See 8/5/18 note below.] To be fair to Brook, it doesn't appear on their confirmed compatibility list http://www.brookaccessory.com/detail/44237976/ --although the Silent version of the same stick does, so I had hopes. : P
Update 9/10/17: I did check with a couple of my older, slower PS3/PS4 sticks, a Madcatz TE and a HRAP 4 Kai, and with the Super Converter they were both roughly 2 frames slower than a native PS2 stick on its own (CVS2 ASCII Stick FT2) in KOFXI, so that isn't too promising as far as arcade sticks go. The HRAPV Hayabusa 2017 is in theory nearly a frame faster than those two sticks, but that would still leave it one frame behind the native PS2 stick.
Update 8/5/18: Updated the converter to the 1.3.1 firmware and the Hori RAP V Hayabusa 2017 works! Have to set it to PS3 mode. No input lag difference between it and the PS2 ASCII Stick FT, so the ASCII Stick can now go in the cupboard, and I can use the RAP V for all my PlayStation consoles! : D So cool! Thank you Brook!
My King of Fighters series playlist: https://www.youtube.com/playlist?list=PLZO3OPzPjIzNvBWZPI5W7JycAiwsVbKgh
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