I have both lenses and use them mainly on a Sony A7s. Both produce nice images, but the 7 Artisans f1.1 has a special character wide open, sometimes the out-of-focus areas look almost smoke-like. Big and heavy, though.
The J3+ is better than most older J3s that I have seen, but build quality still feels somewhat sloppy on the helical on my copy. Number markings on the lens are way too small. Images are somewhat similar to those from an Opton Sonnar. Feels small compared to the 7A.
Neither of my copies has the outstanding micro-contrast of a newer “premium” lens, such as the Sony Zeiss 55mm f1.8 Sonnar or a modern Leitz lens, IMHO.
As far as bang for the buck value, both are good, but if I had to keep just one, it would be the 7A.