Hey,
Auto-email is probably one of the most important features for review apps. As Matt pointed out - there are several alternatives to Shopify's reviews app. Since you're in the fashion business - I'd love you to check out Loox - Fashion Reviews (https://apps.shopify.com/loox-fashion-reviews).
Loox automatically collects rich visual reviews from your customers, shows your visitors how items look, fit and feel on various body types, and helps visitors overcome size & fit concerns.
Hope this helps!
Yoni