Ok, I’m pretty sure people on this forum have confirmed the 1st-party wireless controllers are lag-free.
Wireless controllers in general are notoriously laggy, but official Ps3 and Xbox260 controllers are an exception, and are recommended.
As an example, most people on this board frown upon retail-avaliable wireless sticks, but Toodles and Gummo have both designed pcbs for hooking up SixAxis (not DS3) boards to arcade sticks.
Here’s the Dragonplus: dx.com/p/ps2-to-ps3-controller-adapter-convert-cable-black-56393
Mixed opinions have been given on this adapter, but the positive reviews tend to cite lag-free operation, while the negative ones refer to general functionality problems. I suspect, therefore, that this is a great adapter with inconsistent quality control.
I should note that it doesn’t seem to work with some DS2 models, but does with most - I had about six psx/2 controllers, and most worked.
This adapter is mentioned in the compatibility thread, btw.
Edit: just watched that video you linked. Not sure what 100% proof you’re talking about. The amount of lag is completely meaningless - anything sub 4-5ms shouldn’t be noticeable for a user. Also, that video is demonstrating the Cronus device, and so does not really give an accurate picture of what we’re talking about here.
In a nutshell, if it’s just lag you’re concerned about, just stick with the DS3.
If you’re worried about the deadzone with the sticks, then I’m not sure what to suggest. The definition for where the stick engages for digital inputs could depend on a variety of factors, such as the ps3’s firmware, as well as being defined differently from game to game.