Freestanding deck - should I use joist hangers or bugle screws to attach joists to the bearers?
It depends on your local building codes, but most places in the US, they will insist on the joist hangers.  Joist hangers are far stronger and safer.  

They are not that much more trouble, in fact they may be easier to work with.  You can put them in half way, set the jousts in, then finish attaching them.