Keep the panel filter, Maxogen won't buy you any bhp what so ever, on the contrary will probably loose some torque too.
-S/S Catback = +3-5bhp
-Sports cat = +3bhp
-Group N = +5bhp
-Inlet matching = +5-10bhp
Bang for buck id get the panel filter fitted, i'd then get the exhaust done, then get the inlet matched, then i'd get it remapped. Should be looking at a healthy 190-195bhp at the fly i'd say. Providing of course your 182 is a 'good' one and isn't down on power to start with.