I have a similar dilemma about the BCP-NRSV combo; I can’t bring myself to spend the $60 on it and have just contented myself with my separate copies.
That said, I do find value in my Greek-English diglot (Nestle-Aland 28th edition/NRSV-REB) and my Hebrew-English diglot (BHS4/JPS), so I’ll do combos when I feel like it’s worthwhile.