Don - KM4UDX
You are giving us all heat sink envy! Hahah. But, as others have observed, the kit heat sink's are fine except in some unusual operations:
- more than 13v to the finals
- full power FT8 or WS
- zero free air movement.
In 95% of cases, just drill some holes for air movement, and/or install a small & slow fan.
I do 20v on the finals and WSPR 24/7 when I don't do psk/Hellschreiber. And I use a fan on a thermal switch.