When choosing a UK casino with a strong slot library, look for clear RTP info...

https://wiki-burner.win/index.php/Why_Does_the_Same_Slot_Have_Different_RTP_on_Different_Casinos%3F

When choosing a UK casino with a strong slot library, look for clear RTP info since RTP reflects long-term returns, not short sessions. Some slots offer varying RTP versions depending on the operator