Spotted this in my latest Costco brochure so it's nationwide - in store purchase only.
No idea of the quality of the seed as I've only bought seeds a couple of times for my solitary bird feeder.
The price looks good compared to an equivalent pack size in Tesco which is £9.00 but I've no idea how this compares to garden & pet centres etc so I'm ready to be shot down!!
PS - just spotted this on Amazon for £20.99. They must be making a killing on this!!