An airside store opened last year at Heathrow. It's great and they are looking to up the game on their coffee / breakfast pastries offer etc in thesde airport stores to compete with the likes of Pret / Starbucks etc
Germany has been an unmitigated disaster as have their previous foreign excursions which they pulled the plug on - India , Far East, Middle East all terrible moves
Aldi and Lidl are fine, you just have to sift through all the crap they sell to find the good stuff . And if you don't mind shopping in a low budget environment it works ok. M&S is a much nicer experience though but you do pay for it which i don't mind .