I am level 100. Pancakes played with some friends and me a good bit a while back so I am guessing he is probably 50-70 or so. I assume Derek just started yesterday, but I am not sure.
If you mean in terms of played levels. I have done almost all of them. I have 23 left all on the hardest difficulty. I would not expect us to be jumping into those though until others had a chance to level up.
I'm actually level 90.
Payday is trucking awesome but only in a group. I remember I had a full group going for Payday 2 ps3 it was one of favorites co-op experiences.