interesting question. i suppose it would be because unlike real girls/genetic girls, shemales aren't judgemental, bitchy etc (all the reasons ive posted in the thread '1001 Reasons shemales are better than real girls', and reasons others have posted). they have all the best feminine attributes that GG's do, and none of the bad ones (periods/monthly 'pussy out of service' feature, mood swings, menopause, saggy boobs, thinking they are superior to men etc), as well as all the cool attributes of men (you can be best friends, interested in things other than shopping/shoes etc) and have a dick they can fuck you back with.
i reckon it would be awesome to fuck a shemale in the ass and give her a creampie, then she can return the favour, fucking me missionary, and looking in my eyes as she blows in my ass :D
so yer thats my 'danced around the question somewhat cos im too lazy to type all the reasons why' answer to this thread