well there are plenty of new items but are any of them worth usesing after your leave and get your normal stuff back

personaly the assasin armour is realy the only item i ended up keeping at the end.

my worst item were the bearclaw fist relativy usless compared to the ballist fist

The Holorifle. It's awesome against your average Mojave enemies, but the downside is that it can only be repaired by NPCs and weapon repair kits. (Even with Jury rigging)