I go to dead orbit. 1. I buy materials for marks 2. I sell the same materials back for marks + XP then, I repeat 1 and 2, without leaving the vendor. [b]Net cost in marks:[/b] zero. [b]Net XP gain[/b]: depends on how long I can stand doing it. (I'm guessing a long time, though, given how often we repeat strikes.) Even if the buy/sell rate was different, you're getting XP for doing nothing but trading materials back and forth, which isn't what XP is for. Like I said in my earlier post, I take no issue with a 2-way exchange of materials. Just take XP out of the equation.