Ahhh... I'm a fool. You were asking about the SAE, I was commenting on the CAE and the FF. sorry about that.
But, in light of the thread, I've found a great little site listing the different ones and has lots of great pictures to help distinguish the difference between them.
The catch, because there is always a catch, is that it is written in Chinese... but I'll give you the walk through here.
http

/hi.baidu.com/wwwz9/blog/item/3cfcfbf27fb2a112b17ec500.html
They are numbered and listed as follows:
#1 Siamese Algae Eater (SAE) - Crossocheilus Siamensis
#2 Garra taeniata - False Siamensis?
#3 Epalzeorhynchus kalopterus - Flying Fox
#4 Crossocheilus oblongus - Siamese Flying Fox
#5 Gyrinocheilus aymonieri - Chinese Algae Eater
I hope this one helps for you purposes of identifying the one at your pet shop.