The l'or ones are £2 at Tesco now but the shelves were almost clear. I got the last pack of strength 8 and found them a bit meh. To be fair I wasn't in the mood for a coffee when I tried them, but was excited to see what they'd taste like.
Either way, it's not a sustainable source.
I like the Red (Strength 7) and the Black ones (Strength 11).