[Amps] FW: Transformer power rating guess(timate) and "stand-off" IR responding thermometers

[Gene May]

In a recent exchange between K2VCO and KM1H, they describe what sounds like to me a good way to test out an unknown transformer's power rating.  I have seen hand-held stand-off, IR responding thermometers for sale at what seem like reasonable prices.  One aims the sensor at the Device Under Test and reads a temperature, supposedly.  These sensors would seem to be excellent to monitor such tests, and any other test where one is concerned about whether something is either being over-driven or under-cooled.
 
I'm interested in seeing whether the cooling I am building into an amplifier is sufficient for the tubes and the chokes and transformers in the power supply circuits.  Do any of the readers of this have any experience with any of these?  Accuracy and repeatability?  Manufacturer name?  
 
Thanks for your help and advice.
 
Gene May
WB8WKU