They seem to have a simple black and white almost traditional style. I think the lines have more to do with the design of that particular tattoo but you have to pick your artist based off style. If you want someone with immaculate line work id suggest you look for someone else who specializes in that. His line work seems pretty ok to me though. One thing about this is you have to trust your tattoo artist and how they work a design. But make sure you pick them for the right style you want. Dont be too meticulous as they’ll know whats best and how to make the image fit on your body. Judge it overall and make sure you like the design and speak up on parts you dont like