Haydee 1 vs Haydee 2. Like I'm somewhat surprised how I found the main character less appealing design-wise when they changed her appearance from this:

To this:

My opinion on what I consider a good Robot girl always has the one common factor, they have to have visible robo-bits.

Shit like Detroit Become Human Androids don't have enough visible robot bits, so I don't really like them (Though they were designed to look human, so I guess that's why). Characters like 2B, while nice and have a fine ass, I don't like her from a robotic perspective.

Robo-fortune, Aegis, Haydee ver.1, and more are prime examples of good robot girls in my opinion,