I was given some flea tablets to trial yesterday,sound good,starts killing fleas within 15mins and kills 100% within 24hrs,small and easy to administer.Thing is my dogs are rarely troubled by fleas,dont know why but i bet its 7 or 8 yrs since i last had any trouble with them although i treat them routinely when i worm them every 3 months.So i wont know how effective these tablets are,has anybody used them before and how did you find them?