Early gender scan

My hubby and I have compromised. I want a 3d scan at some point (he didnt). He wants to know sex of the baby asap (I don't care so long as it's healthy). We found a place that will do a gender scan as early as 13 weeks...and they guarantee 99% accuracy and if they tell us the wrong gender we get our money back. So I guess there's really no reason NOT to do it.

My question is....when do you think it'd be best to schedule it? 13, 14, or 15 weeks? (It'll be more like..ALMOST 14, 15, 16 on days we are free though) or do you think it won't really matter? I can't find solid info on Google lol so I'm asking for opinions.

We have our regular scan with OB at 20 weeks if that helps at all...

**I should mention it's a 3d scan**