I try my best not to re-use stock, but eventually I'll be tripling them ;D
I use these Stock providers the most:
:iconlakela: :iconwindfuchs: :iconwincey:
But I also use these guys a lot or just found them!
:iconkhalliysgraphy: :iconlivinja: :iconn-nikita: :iconshitani: :iconwind-princess: :iconwolfenphotography:
I very rarely actually browse through DA, I normally look through the accounts I already have listed.
I also use these for other things, but I also browse DA for these stocks:
Backgrounds: :iconburtn: Textures: :iconsirius-sdz: Brushes: :iconredheadstock:
Hope to see those I follow using them, I've seen plenty so far!