Today I put K-Seal into the radiator of my Fiat Panda. The system has been leaking a litre of coolant in 8 or 9 miles, and it has become just a pain to keep topping it up. The radiator isn't leaking, the leak is coming from somewhere around the engine, but I can't see exactly where.
As of this evening, the K-Seal seems to have worked fine. I can't see any leaks. I haven't checked the coolant level, because it's now pouring with rain outside. I'll check it tomorrow.
Yes, it's fine. Drove to Exeter and back yesterday, 120 miles, and I've just checked the coolant level. Top-up not required.