gender determination at 13 weeks.

Hello all, I wanted your thoughts on gender determination at 13 weeks. In my area there's a well respected and popular facility that has 100% accuracy at gender determination at 13w2d. A lot of my family and friends have done it and it has always been correct. Just curious as to why it isn't talked about much on here. Is there not many of these places in other areas? Since it's elective, it's not covered by insurance. It's $79 which can be worth it to you if you want to know 2 months sooner! I can't wait till my appt in 4 weeks!