I don't have a problem with her showing you a rough estimate of his size, you did ask after all, but after suggesting he is bigger than yourself, to go on and point out that she feels bigger is better, and that bigger hits all the right spots, I dunno, I have a hard time not reading that as her suggesting he was better than you, after all, she did make it clear she thought you were smaller, not bigger.
That in itself isn't so much of an issue, rarely are two people together based on sex alone, and those relationships generally fail anyway, so no harm done if that is the case, it'll just speed things up a little. What is an issue is if you don't tell her how you heard those words and the meaning you gathered from them and that it bothered you. If after you've explained, and she's counter explained and you've come to a point where you are both happy in the knowledge that you now understand each other, she continues to make such comments, then there can be no denying that at best she is an insensitive bitch (much like a man would be if things were reversed and the topic was boob size for example) at which point, you can either be a man and walk away, or be an asshole and get your own digs in before walking away, but doing either before you've reached that point would just make you a little pathetic.