shmups.system11.org

So far, no one has beaten Inbachi in the arcades. KTL-NAL is one of the best shmup players in the world and you can watch him practice and attempt to take Inbachi down here:

https://youtu.be/WzsG_MbzvW4?t=4902

Perhaps the arcade has a tad bit more slowdown, but I think it will be years before someone beats it. Also, is this a Progear counterstop?

https://www.youtube.com/watch?v=w-pMuwGErko

Inbachi has been beaten in practice mode, on rank 0. Other than that we don't know much, maybe some guy beat it. There is still no legit recorded full run with an Inbachi clear as far as I know.

For the Progear video, it's a TAS realised by the world record holder.
He explains in the description that usually, it's not possible for the jewel counter to go above 999 999 (if you watch some runs on hoge_master's channel, you'll see him reach that limit at the end of the 2nd loop).
But when you loop the game, the counter is doubled and in this case it's possible to go through that limit (this requires an absurd jewel counter at the end of the 1rst loop that is still not really doable with human execution).
And if your counter is above 640 000 at the end of the first loop, it will go above the internal limit of the game (which is 1,28m), causing an overflow, which allows you to counterstop the game.