So I tried buying some but apparently each waitrose store gets 8 boxes at 8am each morning and they sell out within 30 minutes! They are 4GBP [US$5.80] a box too. Insane!
I went to waitrose again this morning and found the last box. They taste like even more tart strawberries, but I agree the "finish" is like that of pineapple. They are really tiny too, about the size of a raspberry/blackberry.
I will have you know that if I hadn't read that one posting of yours, I probably wouldn't have felt so compelled to check them out. [Thanks Andrew! :) Surprise comments like these make me feel warm and fuzzy.]
For proof, here are the photos he sent me! (posted with his permission)
Thanks for reporting from the UK, Andrew!