Balloon rams are a man made variation of the regular ram for their odd shape. As delicate as rams are, balloons are even more so. No way would I spend the extra money for a balloon ram b/c they're so much more delicate.
Sexing - the pink tummy is the clue that I found easiest to spot. Also, on my male, proportionately, the pelvic fin is MUCH bigger than on the female. My female has the pronounced black spot with the blue spangles but my male doesn't have much of a spot at all. My old male that I had didn't have very extended dorsal rays, but my new one does.
It really is easiest to look at a whole tank of rams and you can see the differences much more clearly.