We use programme Plus injections twice a year on all our cats except our 3 darling unhandlable ferals Masters Ace, Blue and Riley who get cornered and Profendered and parents wear welding guantlets and full body armour
We use Millibex and large Drontal as some of our boys are 7 and 8 kgs at full furryness and we keep a spreadsheet as to how they were wormed as ferals can be quite untrusting if they think you are giving them if something is not normal - I have 25 ferals here at the Clan ranging from nasty to nice
I use Panacur granules in wet food for my outside ferals and it seems to work they are also trapped once a year just to check they are all well and if they are on a good day we pop them to the vets in the trap where they are knocked out and given the once over a quick Program and booster - some let us trap them others don't!!!