Check the new drugs out on NOAH, the active ingredient in Frontline is Fiprinol so any other product with that ingredient works in the same way, although I've found Effipro to be more sticky, which I think makes it adhere to the cat better than the oh so runny Frontline. Maybe thats why it has been 100% successful here.
As for house fleas, I insist on Indorex whih kills the adult flea, larvae (tiny white maggots, size of hunreds and thousands) and disrupts the life cycle for 12 months. The boys are just starting to scratch now, they were last treated in April, so this combination of Effipro and Indorex is perfect for us.
I will say that we have very few (washable) rugs in our home, no carpets, which does ease the situation enormously. Although its less cosy for humans, it means I only need to treat their beds and our soft furnishings with the flea spray as indoors is a safe haven from the biters.
I still use Animed Direct for all my meds and flea sprays, its cheap, fast and reliable. They have Rip Fleas too, which seems to boast the same properties as Indorex, so it sounds like it should work, Dawn.
http://www.animeddirect.co.uk/indorex-household-flea-spray-500ml.htmlIf the cats still have fleas and you don't want to use another topical treatment just yet, try Capstar. One tablet crushed in wet food kills all the fleas on the cat in 24 hours and may resolve your current crisis. I've seen excellent results with this product which I use on my ferals and strays prior to trapping - by the time they get to the vet for neutering they are always flea free.
http://www.animeddirect.co.uk/capstar-tablets-for-cats-and-small-dogs-6-tablets.html