Late to the party. Finally got my first streamer over the weekend only to discover the compressed hell that is internet radio, no better than my Pure digital radio in the dining room. Today I decided to Google "high quality internet radio" and discovered Radio Paradise. Then I found this thread just now.
I think the sound quality on RP is very good, obviously source dependent which varies greatly between tracks, and the music selection generally agreeable with a few lapses. Given my previous diet of compressed internet stations, dull DAB and nice but rolled off FM (on a vintage Sony tuner), the wide bandwidth, especially HF air and extension was a bit of a shock.
The fact that it is listener supported/ad free, and best of all, free from radio announcers with a sense of self importance (yes, that's you 6music) is the icing.
Thanks for the other suggestions. I'll explore these when I get tired of RP. Only been listening since this afternoon!