Melody and Kenji are great hosts and their airbnb is lovely. For perspective, I was working remotely for the month and wanted to be away from the city/people and just take it easy.
During most of my stay I used the bus system to get around and it was really pretty good. The bus fare is basically $5.50/day unlimited trips with a Holo card (max $70/month), there is a stop at the entrance to the airbnb-building's parking lot and between google maps and DaBus app, I was able to navigate to almost any part of the island I wanted to go to. I did rent a car for the a week of the trip so I could make sure to get the areas that were a bit more of a journey, but the bus was fine the rest of the time, and was very convenient for getting to and from the airport. Distance to The North Shore by car 1-1.5 hours, by bus 2-3 hours; to Honolulu/Waikiki by car 45 min, by bus 1.5-2 hours.
Makaha Valley is very out of the way for most of the island, so that results in a very relaxing feel to the area. There are local restaurants and grocery stores within 5-10 min and maybe 30 minutes to the more suburban-type areas with all the typical retailers. There is a bit of construction happening on the only road into Makaha Valley, but I only hit really bad traffic twice, the rest of the times it wasn't anything too crazy.
The airbnb itself is great. The bed is comfortable, the AC works really well, the wall of glass is simply amazing with the view. The internet speed was great, I was getting 100mbps download speed, so no issues using zoom or netflix streaming. The kitchen has a good selection of pots, pans, etc. Plan to pick up toilet paper and possibly other daily items (paper towels, dish detergent, trash bags, etc), as the hosts make sure you have a "starter" amount, but will likely need one or more before the end of your trip. The coin-op laundry facilities are right down the hall and it's about $1.5/wash or dry, the machines are pretty nice too.
I would definitely be happy staying here again. I possibly would look at staying a little closer (driving distance) to the North Shore on a future trip, but its really hard to beat the vibe and value of Makaha Valley. If you are wanting to go all over the island throughout your trip, this might not be the easiest place to do it from. However, if you are looking to get away, and are fine getting around on the bus or don't mind paying for an uber or rental car when you need it, then I wouldn't hesitate to stay here.
Some reviews have commented about the security personnel being rude, but that wasn't my experience - all but one of the security people I interacted with were very nice and helpful. One lady was not pleasant, but otherwise, the staff for the property are great.