Not fads, the t50 that are nice to put out farms join synchronized t50 farm decks:
http://elementscommunity.org/forum/index.php/topic,20630.0.html
Check out the dates when the next rares come out.
Currently it's Owls Eyes/Vampire stilettos.
The two t50s I know that mostly follow the schedule are 10 men and deepdown.
That is useful to know. Thank you.