Yes I have. My favourite combination is:
Brimar 12AT7 black plate
Tesla ECC803s x2
GE 5star 5751 triple mica x2
This produced the best mix of detail and warmth/body.
Brimar 12AT7 black plate
Tesla ECC803s x2
GE 5star 5751 triple mica x2
This produced the best mix of detail and warmth/body.