I have this one, have yet to power it up... maybe I should,, there is plenty of review of this unit on youtube.. from Non-Chinese person... it works.. and there is some corks and kinks on it if you use a soft start power supply.... you'll have to use two switch.. one for the power supply one for the induction heater... you have to wait for the power supply to come up to voltage before turning on the unit.
As far as the miniductor I do have their MD-710 unit and can definitely say it works... sort of.. only when you can warp the coil around the nuts if you can't, you might be there for a while, and definitely you won't be doing it on the side like what's on the video...
https://www.ebay.com/itm/1000W-ZVS-...-Module-Flyback-Driver-Heater-US/173183297050
There are these new ones I am eyeing on.. 2.5kw claims.. not sure.. will see... it doesn't come with a power supply unit... but I have plenty of 24V 48V power supply stuff...
https://www.ebay.com/itm/ZVS-Induct...river-Heater-Tesla-Coil-Dual-Fan/254173412163
This is the video I found very comprehensive..from a more knowledgeable person than me...