What bait you use makes little or no difference. It's the active ingredient, which has to be written on the container that makes the difference
1. Warfarin. Still works but you may find that you need larger quantities. Added benefit of using this bait is that is has no secondary baiting effects. Some areas do have warfarin resistance but certainly not all. It is usually down to baiting techniques. Outdoor use authorised
2. Bromadiolone. Good second gen bait. Once again some resistance but only in tiny pockets so your unlikely to hit it. Outdoor use authorised
3. Difenacoum. Good second gen bait. Outdoor use authorised
4. Caliciferol. Good second gen bait. Very expensive. Hence mainly used in mouse baits. Outdoor use authorised
5. Brodifacoum. Very effective bait. Illegal for use out doors and if used incorrectly can cause bait shyness. Pre-baiting is an essential technique used with this bait.
6. Alphachloralose. Magic bait that if taken in the right quantity has halucinogenic properties
. It is only effective though in lower temperatures as it shuts down your ability to control your body temperature so you die of hypothermia. Antidote easy though, and nice warm room.
7. Eco friendly products. They are out there but I've had little experience of them and what I did wasn't great.
It mainly comes down to technique. Apply the bait in as secure way as possible as close to where they are living as is possible.
I used to bait first, then check after 5x days. If bait gone then re-apply at double quantity and then check after 3x days. If after 3x days bait gone then double quantity then check after 3x days. Keep doubling quantity of bait until you get some left and then maintain at that level until you start to get a drop off of bait taking. When bait taking ceases then you can drop off your number of visits.
The secret to any baiting is not to stop.
I used to use upto 150kgs a day when I worked for the council. And one year I worked out that we used 5 tonne on all our contracts.