I've never bought a box of them. However when you place an order with Zero you can ask for samples of something you'd like to try & I asked for some of the solid bullets once. (They usually send you about 20 bullets of each type you ask for.)
I had a bunch of extra gas checks so I added them to the bullets, since they have a nice flat base, & loaded them with 5.5gr/Unique & seated them to a COAL of 1.587". They did fine, nothing special, they shot POA=POI.
They are soft but probably about the same as Rim Rock's 158gr LSWC-HP-GC which has a BHN of 5.
Worth trying for SD loads, with some gas checks added, if that's what you like.
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Zero 158gr LSWC-FB
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