in terms of both ... and ...; whether it be ... or ...
Pattern: AといいBといい. Used to list two aspects, both of which support the speaker's evaluation. Often implies 'not only A but also B' or 'both A and B are ...'.
このホテルは、サービスといい、立地といい、文句のつけようがない。
This hotel, in terms of both service and location, leaves nothing to be desired.
彼は、性格といい、能力といい、理想的なリーダーだ。
He is an ideal leader, whether you consider his personality or his ability.
にしても means 'even if' or 'whether or not', while といい emphasizes that both aspects share a quality.
Derived from the quotative particle と and the verb 言う (to say), literally 'saying ... and saying ...'. The expression grammaticalized into a fixed pattern for listing evaluative aspects.