Finilec is no good if you've got a gash in your tyre John. Most types of the foam stuff you get instead of a wheel is useless. Some of them are 'glue' based, this means that as well as temporarily repairing the puncture, they glue the tyre to the rim so that when you go to get the simple puncture permanently repaired, the tyre fitters damage the tyre when trying to remove it from the rim. So instead of a simple repair, you now need a new tyre !. We use 'Slime', which is an American water based product. This can be washed out when the tyre fitters permanently repair the tyre. Unfortunately though, you still need a foot pump or air compressor. Some time ago, Rover removed the spare wheel from the '75' model. There was such an outcry that they re-introduced it !
I agree with the foam type stuff - keep well away!
To complicate matters even more, you can't have different circumference wheels on the front axle, as they destroy the steering geometry, and will cause the remaining tyre to be out of track, and go bald, over any distance, on it's edge, if you drive a rear wheel drive car. (As you can't use the spacesaver on the front anyway if it is front wheel drive); and it's true about spacesavers being totally useless on a 4x4, and when using a spacesaver, you aren't allowed to drive over 50mph, but the crowning glory is DRUMROLL..........
It's ILLEGAL NOT to carry a spacesaver! If you break down on the motorway, and have to be towed, due to tyre failure, then you are fined, for not carrying a spare. I think it's an £85 fine, (plus recovery), as not having a serviceable wheel, ie your rim might be damaged, and the vehicle untowable.
Daft laws that nobody knows! Did you know that it isn't a right to drive on the roads, but a priviledge, as it's the Queens highway, even though you passed a test to get a license? A bus stop is called a clearway? A bus stop in a bus station is called a stance? Most road marking are marked incorrectly, but appeals are upheld? Due to the camera angles used by wardens? There is no law that says you are allowed to park outside your own house, but strangers can, but not block your drive? But if you block a car parked in front of your house, then the police get involved? And seemingly have the right to take control of your vehicle and break it. (Bitterness there!)...