I agree with Charles. Use them judiciously because they are expensive but extremely neutral. I have a pair in the first stage signal path to my MC step up device (Hagerman Piccolo), but I found I needed something bit "fleshier" as second and last resistor int he signal path, so I went with Riken's there. But you have to be careful to use Riken's judiciously too or things can get muddy. This pairing gave me what I wanted overall.
I've also used the also expensive Caddock TF's and in general liked them better than the Vishay's.
Bob