these gouramis can be fickle fish at times. ive seen very placid and rather aggressive gouramis in blue, opaline, three spot and golds. my personal advice would be to try a female on the understanding that if there are aggression probs (i would put the odds as high as 50/50 from what ive seen on forums and in my own tanks) the fish shop will be happy to swap dfor a male or refund you or at least give you credit.
i guess you know how to sex these fish? if not a quick reminder.
the dorsal fin on a male is pointed and one a female it is rounded. young fish are harder to sex.