The Thunderbolt Plus 1200W has an ace up its sleeve and this is of course the iPower meter device, through which enthusiasts can continuously monitor system power consumption, voltages etc. Unfortunately it seems that the iPower meter needs some tuning because its readings are not too accurate, especially the voltage and efficiency readings are way off. On the contrary the Ampere readings on the minor rails are quite accurate and the same readings on the +12V rail are not so far from the real values, especially at lower loads.
Voltage regulation at +12V is decent for a 1200W unit, ripple suppression on the same rail could be better, voltage regulation at 3.3V is pretty loose and efficiency in the 20-100% load range is high but not that high for Gold standards. Also two things that most likely will annoy most of the unit's future buyers are the fan that makes its presence well felt at full RPM and the large number of native cables. Personally I would highly prefer to see less fixed cables and more modular ones.

To sum up, the Thunderbolt Plus 1200W is an expensive PSU which, like all consumer products, has some set backs but also has enough strong points like very good build quality, exclusive use of Japan caps, flawless operation even at high ambient temperatures and really compact dimensions for a 1200W unit. In my opinion, in order to be a far better product and earn my recommendation it needs the following fixes: tuning of the iPower meter device in order to be more accurate, a lower price and a quieter fan. Better ripple suppression at +12V and tighter voltage regulation at 3.3V would be the cherry on top for me!