The Octavia 3 has option extra of space saver or spare wheel. Why would one choose a space saver over spare wheel?

Is there a cost difference?

 

(And for an Octavia vRS, it has to be the space saver, because the brakes are too big for a standard spare. Until they recently reduced the size of the brakes, but that's another story)

Either one will require you if fitted to reduce your speed while temporarily fitted unless the Spare has a matching Tyre to the one on the same axle.  Then get the damaged tyre repaired or replaced, and change back.

 

Maybe worth buying a Spare Wheel / Tyre that matches the other 3 if it fits under the floor, which likely it will.

If you have Directional Tyres on there is a 50% chance it will be for the correct side of the car when put on.

Take the cheapest one.

 

It's for emergencies.