。
She's got really great taste, you know.
Literal
She [topic-は] high-sense [genitive-の] possessor is [you know-よ].
ハイセンス ('high sense') is wasei-eigo — a Japanese-coined pseudo-English compound meaning 'good taste, refined sensibility,' which doesn't exist in English with this meaning. The native Japanese センスがいい conveys the same idea more conversationally; ハイセンス sounds slightly more stylish and brand-conscious. 持ち主 ('owner, holder') paired with an abstract noun like ハイセンス gives a faintly elevated 'a person possessed of X' nuance, more flattering than the simple ~がいい. The sentence-final よ is informational — the speaker is letting the listener in on something they may not have noticed.