I kind of gathered from your username that you would be familiar with the Benedictine Office! I agree with you about the Pius X psalter… yet I’ve had heated arguments on CAF with self-designated “traditionalists” who insist it is a “traditional” breviary. Not!
I have the 1934 Antiphonale (as well as the '35 Antiphonale Solesmense, and 1895 Liber Responsorialis, and God knows how many other liturgical books and breviaries; the Pius X is one breviary I do NOT have LOL!). Which brings up a practical reality. I can’t imagine there are too many pre-1910 antiphonaries and breviaries in circulation these days, whereas the 1934 Antiphonale is still in print by Solesmes. So either communities will have to put together in-house adaptations, or, more simply, adopt the Benedictine as-is without doing too much violence to Roman tradition as the two breviaries are so similar, a big exception being psalm 11 on Sundays in the Roman, and on Mondays in the Benedictine.
I can see the use of these breviaries by communities or chapters of canons, but not, alas diocesan clergy, given their declining numbers and increasing workload. The LOTH is here to stay for them. But even in communities, the Benedictine or Pius V offices are very heavy. The abbey I’m attached to had 42 monks when I made my oblation in 2003. They are now down to 26, and Vatican II abolished the distinction between lay brothers and choir monks, so all the monks participate in the abbey’s workload, which is not obvious for 26 monks with an average age of 70, with many in their 80s and even three or four in their 90s.
I myself pray a post-conciiar breviary, monastic Schema B (all 150 psalms per week with one variation, I divide Vigils over two weeks and use the psalms of Compline for the second nocturne, so that I can use psalms 4, 90 and 133 every night at Compline; this variant is in the General Instructions). I have no particular affection for it as it does even more violence to tradition than Pius X; but it’s what the monks of the abbey I’m affiliated with as oblate use. First and foremost I want to pray in unison with my community. When I do get too busy or tired, I use the LOTH, but do it all in Latin and in Gregorian chant. For Schema B, I do Lauds, Vespers and Compline in Latin Gregorian chant, the rest in French plainchant (recto-tono) with Latin hymns in Gregorian chant, following the practice of my abbey. One other reason I use this breviary, every Wednesday I volunteer as assistant librarian at the abbey library (I’m retired from paid work). So while I’m there I obviously attend Offices and Mass with the monks (their Mass is OF but also in Gregorian chant). For continuity, it makes sense for me to use their breviary.
(to be cont’d)