This is more advice AGAINST a particular brand of groundwound/halfwound string - I bought some Rotosound halfwounds and I was personally quite appalled by the quality! The feel was HORRIBLE, for example when trying to execute double stops on the D&G strings the strings would 'grip' onto the pads of your fingers

some application of fast fret exasperatingly made it worse
They sounded positively O.K in the beginning and almost sounded quite...'bland'(?) as they died down. Just didn't like them at all.