Check her out on Tennessee Waltz and When I fall in Love. You can compare her with her US counterparts, and she more than holds her own. Just because she sang a lot of rubbish (which gave her hits) should not disguise the fact that this was a talented lady who died before she could build a reputation as a "serious" artist.
I just want to second the views of 1969SL: Alma was a very decent talent coming up in a musical culture (British pop music in the early 1950s) which was totally second rate. She had a voice along the lines of Brenda Lee and Connie Francis, but (from my memory) had to make do with second-rate material. I seem to remember that the Beatles rated her, and I suspect the problem with her is that she died relatively young, and never had the chance to demonstrate that she could cut it with more mature music. I seem to remember a BBC4 musical biography of her, and I was impressed. Everything she sang, she sang well. In her context, she was good.
The biggest UK female pop star of 1950s - died at 34 from cancer - remembered as being ultra-glamourous and elegant in her time (even Queen Elizabeth was impressed with her dresses) and slowly through the time other pop stars overshadowed her memory,today hardly remembered except for faithfull audience from her time or curious listeners like me.Besides obvious bubble-gum hits (cheerful,Doris Day-like happy ditties),she also recorded several LP albums with swing/ballads standards and who knows how her career would developed (probably big spectacular TV shows and such) if not for early death.
Very attractive lady,I don't understand insensitive remarks here - we are talking about entertainer from 1950s and fashion from that time - perhaps you should hear her voice and think about what you are saying.