There is a quite long list of all available TDCS devices and their specs available on that subreddit . It such a niche thing that there isn't much bias at the moment

After all a TDCS devices just sends a specific current for a period of specified time .

Whatever brand's marketing can get in there first, snag a moderator role, and then flood this discussions.

True for everything, and is why I pray for the Dead Internet Theory to happen.