6H30 tubes vs the others

I have a CJ CT-5 which uses the same tube. Prior to that I owned a CJ 17LS which used the 6922 tubes. Partly depends on what your after. Tube rolling offers many benefits (and frustrations too) but ultimately keep your focus on the preamp itself and not the tubes its uses. Trust your ears, if you like what your hearing you'll be fine. BTW, those BAT preamps are great. Well built with great support if you ever need it.

Good luck

The 6H30 is considered one of the least "tube" sounding tubes. That is a generalization, of course, but many people don’t like preamps that use it for that reason. Other people seek out preamps that use it. They think that it provides some of the beneficial aspects of tubes (e.g. more 3D imaging)  with less of what they consider tube colorations.

Audio Research also uses the 6H30 exclusively. I haven’t heard either company’s preamps but I think they probably sound different. You’re probably better off trying to figure out the house sound of different companies’ preamps and which might appeal to you. The best way to decide is to listen to different preamps, if you can, of course. I don’t get the opportunity to listen, so I’m like you. I try to figure out how they sound by what people write about them.

Also, I like to tube roll, so that keeps me away from the 6H30.

The military grade (DR NOS) 6H30 is a truly great tube. These were manufactured pre Y2K (year 2000) and are scarce and very expensive ($200 - $300 each). That said, the quality of current production is mediocre (sound and durability). There is a large market for high-quality 6H30s and I've mentioned this to the new Western Electric tube factory in Georgia (U.S.A.) (no reply).
The basic design of the 6H30 is ideal for audio.