My wife and I had a great 8-day stay here with our two young kids and my parents. The location was unbeatable -- a short 1 block walk to an outrageously beautiful sandy beach that is shaped like a C, bordered by large palm trees and ends on both side with large rocks and trees. It seems to be a popular beach, but even so it was never crowded for us and was great for swimming, reading, playing in the sand and watching sunsets. One side of the beach is relatively calm and great for young kids (it gets deep quickly though - we brought a life jacket for our 4yo who can't swim yet, and that came in very handy), and the other side has bigger waves for older kids who want to boogie board. A friend who grew up on Maui told me that Napili Bay is her favorite beach on the western side of the island and it's not hard to imagine why she thinks that.
The Sea House is a wonderful restaurant with reasonable prices (given the location), especially for breakfast/lunch, that is right on the beach and very convenient for walking to/from the condo. There is also a great surf shop (808 Boards) nearby that carries everything you need for the beach, and a medium-sized and well-stocked grocery store (Napili Market) is a 2-3 minute drive away.
The place itself was very comfortable for us. Parking was easy, check-in was easy, beds were good, bathrooms were great, cleanliness matched the pictures, kitchen was well-stocked with both equipment and spices/cooking essentials, A/C worked well, furniture was very comfortable, etc. There were a lot of beach toys/towels in the garage and useful stuff for small kids (high chair, pack-n-play, kids toys for indoors). I never think about washer/dryer availability when looking for an Airbnb, but the ones here are great and we ended up using them quite a bit. Our only knocks against the place are that the wifi was patchy at best (the host suggested some improvements but they didn't really work) and there were some maintenance / wear and tear issues on the back patio. If you are going to need/rely on Wifi access during your stay, it may be worth checking in with the host before booking to see if any changes have been made.