Cheating and collusion are more difficult for a player to spot on anonymous tables, but they are WAY much more easier for the network/site to spot (if they have the tools).
For obvious reasons (I work as acting head of poker on a competitor to Betsson in the same network), I cant comment if Betsson is good or not, however the network (Microgaming) in my honest opinion is really good. From a pure financial perspective, Betsson (who also owns Nordicbet) is listed on the Swedish stock exchange main list, so you dont need to be afraid that they will take your money and run. Neither would the site I am representing, since we are owned by the Ålandic state (however we have not gotten the license (yet)).