As I said, we have lots of the huge black and orange ones and we leave them alone because we understand that they eat smaller slugs more than they eat plants.
In the 18 months we've lived here I've honestly not seen more than half a dozen other slugs (if that) and we've really not had any slug damage that I've noticed, despite growing hostas and salad veg amongst other things.
We've had some snail damage (one got into the cold frame and munched on some basil seedlings - there was also some snail damage on a Cos lettuce)
That really has been about it - I think we're lucky with the gritty nature of our soil (a sandy loam) - don't think the slugs like it - and of course we have resident hedgehogs and also encourage lots of birds into the garden, and I understand that the previous owner here gardened organically for 30 years.
I'm not going to waste my money on slug killer 