Thanks David, I really appreciate your input. Maybe I should go for non RFTs. £460 is pretty much the same cost as a vanity plate or an engine chip after all. I don't mind doing some emergency work at the side of the road. That blow out I had was the first time I've ever changed a tyre and it was on the side of the M25 (probably the busiest motorway in the UK). Using a plug kit on the side of a relatively quiet snowy road is probably more fun than changing a tyre on the side of a busy motorway with juggernauts zipping past a few feet away!

Are the plug kits better than the tyre weld type products that you spray into the inside? I'm guessing the plug kits are a bit more effort but should last the life of the tyre compared to the tyre weld stuff that's more of a temporary thing but is easy and quick.