Go with the Remington 870, a lefthand safety can be installed for those that need it.
If you start looking at safety's the tang mounted ones require a change of grip, moving the thumb, to operate. A trigger guard safety, like the Remington and others, requires only moving the trigger finger from the safety to the trigger. Thats why the police like them.
Both guns are well made, BUT there is no comparison to a 870 Wingmaster.