Hi - The first few comments are from what I term "highly respected" members of this forum - and I am more than happy to take their advice/comments on board. I did kind of suspect that it might be a case of quantity over quality, but on the other hand didn't want to miss out on a bargain if one was to be had.
So - I will be on the phone to my supplier on Monday and get the real deal. When I think how long the old blades have lasted (I use them a heck of a lot) I guess they don't work out expensive at all really.

Once again - many thanks ladies. Yiayia