Yes, I plan to build the "Damn Good 300B" PCBs from Neurochrome.com, with Electroprint stranded silver plated copper winding transformers and Black Treasure 300Bs.
One thing I'm concerned about is the beaming highs. I have them ponting almost straight at me to get full extension. I can tweak the zobel filter to increase the highs, then toe it out a little, but it's still tweaky and then anyone sitting on beam would be uncromfortable. So I might add a dome tweeter at 5k with 1st order crossovers to broaden the HF dispersion. If I put a tweeter above the FR driver, then I wouldn't need a pedestal to lift the FR driver higher. I'd probably go for the SB Acoustics SB29RDNC. 94dB sensitivity, 4 ohm, neodymium, dimple dome, like on my Satori tweeters which I love.
The bass is suprisingly good now that they are mostly broken in. Bracing is up next. I have an elaborate bracing scheme, but braces take up box volume, and they may shift LF vibes up into more audible HF range. I also don't want to over do it and stop all the lovely woody sound, so I will start with just a few cross braces wedged in tight and see how that goes. Then add some loose pink 2" FG.