I finally had break where I could fiddle around with my gear a little, so I put in some Tung Sol 5881 RI's and a NOS 5751 in my OTS to see what they would do. I was skeptical about both since I have not had good experience with either Sovtek or Tung Sol 5881's in the past. I also was not terribly impressed with the 5751 in V2 of my Super Reverb.

However these tubes in the OTS (5751 in V2) seem to work great. They do take some of the buzziness and highs out, that I usually have to tone down by other means. I think this is a good option for some folks, especially if you have the s&m OTS.

This also gives me hope that the TAD 6L6WGC STR may be a really good fit for the OTS. I had tried them as an upgrade to 5881s  in my Bassman, but they did not sound a whole lot different (not too good). They did sound great in my Super Reverb but only lasted about 6 months.  They are little more musical than 5881's but are lower powered than 6LGC's.

A good alternative to the 5751 maybe the JJ ECC832. I have one, and may give  it try.