By volume, probably the old dudes who are doing it for years here. Like SebastianJu,Minerjones, OgNasty, etc.
By the most trustworthy, well the same guys, if they're still doing it, there is a reason :p
You can find some topics here and there to search through

edit: like this one: https://bitcointalk.org/index.php?topic=2439910.0