I've been building amps and preamps with DHTs since around 2009, and been through many of them. I took time off to explore a 2 stage amp with 2a3 outputs and 6SN7 variants as driver stage, liking the CV6 a lot. But I've started putting a preamp in front of my 2 stage 2a3 SE and I'm trying out DHTs again in my modular system, which means I can build quite quickly with existing parts. I passed over the 26 this time and liked the 2P29L better. Then the 6C4C which I liked better still. And latest is a 10Y preamp which is very nice. I also tried a 300b preamp but that only lasted a few hours before I was bored by it and changed it to 10Y. Too smooth and euphonic and not enough detail and bite. The 300b for me is quite like the 26, a pleasant sound but not as involving as other DHTs. I have 2 variants of 300b, EH and Chinese 4300 from a while back. Maybe I'm not hearing the 300b at its full potential but I clearly prefer the 2a3 and Svetlana 6C4C - more focussed sound, more involving. For a preamp I could listen happily to 6C4C or 10Y or indeed 2P29L. I haven't got round to trying 46 or 47 but have both and will be trying them. In the past I could prefer the 46 to the 10Y but it's been years.