I buy all my strips from ebay in sealed packaging, with long expiry dates. I have never had a problem from business and private sellers. I can usually buy all my strips for less than £10 for 50 when the RRP is £25.
When i first started using the forum many type 2's did this before codefree became popular. Over the 6 years I have been testing the number of strips purchased that have been prescribed (removed sticky labels give you a clue) have reduced to zero.