It's rather sad that someone would feel so insecure that they think they need to have a specific type of vehicle to attract a female. The type of female that would be attracted by a vehicle is not likely the type you'd want to attract anyway.
Actually I'd say show up in a beater. If she goes on a second date with you, then she's a keeper.
I kind of agree here. You don't want pretentious, or overly image conscious. But the beater can't be so bad that she would be embarrassed for you to drive it to her families gathering.
It also depends on age. A college or post college age, beaters make sense, If you are 50 and drive a beater on a date, that's a different message.