Please send us your suggestions for Great Britain and help others to get a reasonable SIM-card for their next trip!
In the UK, there are 4 network operators: EE, Vodafone, O2 and 3 (Three). These use the frequency bands common in Europe.
Prepaid is most commonly referred to as "pay as you go (PAYG)" in the UK.
With all Internet access in the UK, only adult content is displayed unless this is explicitly deactivated (with proof of age). However, quite common services often fall into this filter, which is why it is advisable to check the age at the time of purchase.
International offers and reseller with international shipping: