Bianchigirll FWIW: I have the disc brake version of the Soma Buena Vista. Their price has come down from the pandemic high of ~$1000 that I paid. So, I would call $700 a good buy if you were on the fence with the idea.
For mine, I ditched the OEM fork & built it up with a pile of weight-weenie road components I had on hand from other projects. It came out to 19 pounds and a few ounces. All in, owing to materials already on hand, the whole project probably set back my lifetime earnings about $2k over not having ventured at all. Very much worth it. It is a supremely well riding and sporty road bike.
My only gripe is that as a bolder than average descender the torsional stiffness does not inspire confidence in negotiating switchbacks at inappropriately high speed. Wide low pressure tires 700x38 slick tires hold the road well, but if only the feedback were less vague between where the front wheel was pointed and the saddle and back wheel followed...
I suppose that characteristic is inherent any and all mixte designs and due to the triangulation between the rear dropouts and the head tube they are a whole mess better than any other low/mid-step design. The mixte is the clear choice for better roadier road bike performance among non-diamond frame designs. (They're just harder to manufacture, thus less common.)
If I were to do it again, (knowing that torsional stiffness is it's only weak spot, (If you are really pushing it)) I'd spec a larger headtube and downtube than the good folks at Soma. For a point of reference, I had a diamond frame Ritchey Ascent that I paid double for & it felt mushy and vague all the time!
All this is to say: "Don't let the $700 price tag scare you. The Buena Vista is a very fine riding bicycle."
I do wish I had input on the Libretas. It is a pretty blue color. What I can't say is whether or not it conforms to any modern "standard." It'd be a shame to spend $250 only to find out there is an Achilles heel with some component made of unobtanium. This is purely my own ignorance that makes me wary. At least the Soma is a known known.
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