The studio is spacious - including a large shower, a decent-sized counter, and enough space from the other studio that it feels private. The kitchen amenities are in great condition, though there are no cooking oils/salts/etc. provided. No space for non-refrigerated groceries. The couch/futon is comfortable for reading and the TV is on a moveable arm.
The bed left a lot to be desired. Queen bed frame, but with two twin stiff-foam mattresses put together. I woke up so sore after my first night that I went to Target and bought a twin memory foam pad and a non-foam pillow. Surprisingly disappointing compared to how nicely the rest of the place is furnished. The kitchen is easy to use: the hot plates are new and get hot fast. Also convenient for deliveries if you want to avoid Waikiki for a night!
Nina's place is very convenient if you're a runner, hiker, or surfer. If you want to go anywhere besides Diamond Head a car is needed. Parking is easy and safe on the street. About 5 min away from public (paid) parking by Kaimana beach. Watching the sunset there is unlike anything else in the world. Gorgeous view from the house's gate, no view from the studio. If you're planning on spending most of your time touring, this place works! If you're looking for a long stay, needs a little tinkering to make it work/comfortable.