Judging from this pic as below...

As usual, Heechul still looks pretty whether he crossdresses or not. Kyuhyun, Sungmin, Kibum, Yesung, Leeteuk, and Eunhyuk look pretty as girls.  Hangeng somewhat looks pretty in my opinion. Ryeowook, get a different hairstyle and you'll look pretty while crossdressing. Donghae, Siwon, and Kangin should never crossdress again. Siwon, you look like Minho when he had his long hair in Ring Ding Dong era. Donghae... you look really weird as a girl. Kangin, you're just too manly to even look like one. Shindong, you look somewhat pretty but you're even prettier when you crossdress as HyunA.

Anyways, that's my opinion. Feel free to post your opinion in the comments below!