Black Bin Bags- best source?

Laydidi

Since Birmingham City Council have stopped sending out bags (March 2013 - check under refuse), I've scavenged the ones laid up over previous years. However, rolls of black bin bags sold in shops are so much of a gamble - the ones I have now are so thin, that they rip almost as soon as you put something in them - so I double/ triple bag. This will be a big pain soon.

Does any know of a good source for black bin bags, that are not exorbitant? I'd really rather not end up with several rolls of black bags from various pound shops, supermarkets etc. Can you help me in this search? What have you found to be good?
Or are you still using free black refuse sacks?

Laydidi

DigForVictory

The Costco tie top black bin liners (thumping great roll, hundred + of bags but caveat cost of membership & I think unit cost around £8) are good solid bags.

Savvy_Sue

Robert Dyas also sell good solid ones in rolls of 100. No idea of cost, but they are quite often on offer.