I've found that its a pain in the ass not having a spare wheel in mine (182 by the way)
The foam that came with the car was crap and, it only seems good if its a nail or similar thats gone through the tyre. If you've got a gash in the tyre thats when you've got problems as the foam just seeps out for the fun of it..
If you want weight reduction, buy a space-saver, but from past experience I'd suggest you dont go without a spare. It's a feckin nightmare