a new element to the promitheus story made me thinking.... a TVC plus a tube active part together is now around $1000. if you add a price of a phono pre in case you may need it (as i do), you are coming to around $1600 or so (sorry i haven't checked a current price for a phono unit but remember it was around $500 ex-shipping).
so, $1600 and 5 boxes in the house, plus 2 extra cables.... not sure this sounds inviting to me. thanks but no thanks. for similar money i would rather go for a full function single chasis (or separate supply) unit on a secondhand market. for example mine EAR 864 (not a TVC, but a decent valve pre with transformer output and MM/MC stage) was paid around $1400 for a mint, 1-year old piece, with excellent resale value.
nick, if you read this, i really think you need to make a strategy for your business and some sort of business plan. idea of an active pre to complement TVC can be interesting to some people but not to everyone who bought a TVC. i think, if you are confident that a combo of a TVC and a tube active part is your definitive answer to the world of audio, you need to make 1 product out of that, to make an attractive chasis and good, ergonomic design. not all of us are natural born hi-fi tweakers and nerds, some of us like a simplicity and easy, plug'n'play products.
you also need to think about the price and to see what cuts are possible - i think that with a $1,000 tag it definitely can't be as attractive as a $340 only TVC. i know you can always produce for a niche market, specialists' specalists, but i think you have a great talent and a good understadning of audio that you need to try to bring your products closer to more people than now, and to develop your business into something that will leave a greater impact on the hi-fi world.
hope you will understand i am writing this because of my wish for your success to grow much more than now.