Buy a better Audio recorder or Better microphone

Im deciding on purchasing better audio equipment but im stuck as to what i should upgrade first. I currently own a rode video mic and a tascam dr 40 and im looking into into buying a rode ntg2 and a zoom h5 but i cant get both at the same time, which do you think i should buy first for better audio.

also im wondering if i should just invest in a $100 preamp as i really do care about low noise floor and if it would be a better value buying that then the zoom h5.