Just got back from 3 weeks in Russia (Kirov and Moscow regions). Withdrawing cash and making payments in shops was a breeze - shop assistants love Monzo! Only one transaction refused to work - Velobike in Moscow, although I suspect their system was down or overloaded! (Yes - I was crazy enough to hire a rental bicycle in Moscow!!! - btw, they have some e-bikes to rent on the West side of Moscow as well!).