What to trust? Closed hardware/software that goes to trash if something goes wrong, or opensource that you can send an agent to debug if there are issues? I'm not trying to diminish JetKVM's product - for $35 its a steal if you don't want to bother with DIY and time involved, but I'd strongly disagree that opensource is less trustworthy than closed product.
ArkKVM is a fully open source product now
I think the software aspects of JetKVM are open source? See: https://github.com/jetkvm
Also they say they are open sourcing the reference implementation of the "JetKVM OS Services" and the firmware of the "JetKVM Mini".
My point is more that it is way easier to make mistakes in source than it is to review said source in a project like this. So, to me, it is kind of risky to use something very green that is meant to be used as a network appliance more or less.