I'm just waiting for them to change xur so we can choose how much of an item we want to buy instead of long pressing each and every time. You know why heavy ammo is a long press and motes of light are a quick tap? Equip your spinfoil hat [spoiler]because ranking up takes waaay longer with motes of light, heavy ammo is the smarter buy but they'd rather you waste your time and play longer. So they made it tapping for motes because that's faster than long pressing despite the actual payout. It's almost like they don't expect people to use math to figure out what gives rep faster, and it's heavy by a longshot[/spoiler]