Nicest and most Ruthless PE Shops

It generally will come down to investment strategy. Ruthless will generally be the deep value guys and nicest will be growth buyout. I will say though, firms external perception will not always be what its like internally. My fund was one of the nice ones but was extremely ruthless internally (i.e. sharp elbowed politics). Generally though PE is a fixed pie where you are constantly competition with other people internally and externally which leads to generally ruthless people.