Both safe for solo women in tourist areas. BB noisier, street food on foot — Jalan Alor and Pavilion side are well lit until midnight. KLCC cleaner, family-oriented, quieter after 11pm. Monorail/LRT between them is easy (RM2–3 per ride with Touch 'n Go). You can split nights if undecided: BB for food energy, KLCC for sleep quality.
Bukit Bintang — Jalan Alor and main streets busy late but well lit. KLCC quieter, fine too but you Grab everywhere for street food.
If you hate noise after 11pm pick KLCC. If you want to walk to food without Grab, BB wins. Changkat side of BB is bar street — stay east near Pavilion if you want sleep.
Stayed BB solo last week — felt fine walking Jalan Alor at 10pm. Just use Grab after midnight if you're tired.