That's upto you mate but I'll never believe a locator is a 'must'.
How are you going to dig through rocks, under concrete, rubbish tips/ piles..... Your not.
its handy to have one
But not a necessity. Yawwnnnn zzzzzzzzz
i will hav a go at digging thru anything, i enjoy digging, and digging throught rubbish tips and such i just wouldnt ferret it simple as