Here's a bit of a topic I've discussed before; take it as constructive criticism.
I don't know how they do these renders. It seems like they only inflate some areas of the model's muscles, but it looks strange that, for example, the biceps are so big but not the forearms, back, or thighs. I think if the fetish is the muscle growth of a muscular woman, it should be done completely; otherwise, it looks a little odd, as if something isn't convincing about the anatomy.
Yes, it's sexy, but it could be sexier. Those of us who like the muscle fetish and female muscle growth would love to see more progress on this with the twins. In fact, bodies with very large, proportioned muscles are sexy. And if vascularity is included, it's even sexier.
I'm not a designer, so I just made a quick edit in PicsArt, but it's to illustrate my point a little.
As a reference, I'll also include a model by the artist Ptitipois.