IMO you are much better off fueling your workout and reaping the benefits of fat loss from the recovery period (which will be much more intense if you can keep your workout intensity at peak levels. Remember the majority of your fat loss won;t occur in the gym but rather outside of it). Also if you plan on doing cardio afterwards it would be smart again to provide at least a little bit of fuel prior.
I must admit I have been testing out working out on an empty stomach (running a CKD) and it has dropped my workout intensity a considerable amount. I still get some lifts in (and cardio is fine, but am on ReCreate atm) but I would recommend you stay with a pre meal for the above reasons.