I really must congratulate you on this video. You've managed to find some excellent singers who I've never heard before and I've seen an enormous amount of these videos. Paul Downing and Larry Hooper are among the most impressive ones. Thank you very much.
I agree. You don't see Paul Downing, or Larry Hooper on many videos like this. They were both great, quality, bass singers, but were a bit unsung, so to speak, compared to the basses of the big name quartets. The Downings were known, but not hugely popular, and Hooper was on Lawrence Welk, and I don't think he did much southern Gospel quartet stuff.
I think Geoff Castellucci has a particularly pretty G1 (captions are amusing in this video...): ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-x3gkL3hoTWY.html
It surprised me, how many of these bass singers were a little bit sharp on the Bb below Low C, and some on the Low C. Most had the range; they just missed the pitch that little bit.