Today I received and tried out Raytheons and Sylvannia GB 5687 and was terribly disappointed.
The Raytheons sounded worst than the stock Philips JAN5687, too mushy and one side was particularly microphonic.
Sylvannia had air around the instruments, but everything appeared to shrink in size compared to the Amperex 7119s.
Note that my basis for comparison is:
>Benchmark DAC1 XLR outputs straight into the Sanders
VS
>Benchmark DAC1 RCA output via SWLP9.0SE into Sanders
i.e. one completely by-passes the preamp which some consider to be more transparent, compared to with the ModWright in the chain. Cables were the same brand pure silver Slinkylinks so that should not be a factor.
The Amperex are more quiet in the background, have more body (presence) and throw and much bigger soundstage than all tubes. In comparison to without the preamp in the chain, the Amperex fitted SWLP had more body and imparted a bigger soundstage, without removing any of the detail present when going direct.
Caveat: this is my personal opinion on what I heard with the tubes I had. It could be that the samples of Raytheons/Sylvannias were lemons, nevertheless, they were not as neutral and extended as the Amperex, IMO, YMMV, yada, yada, yada.