We stayed at Slavko's condo for a Technical Exhibition at the Hawai'i Convention Center. We had a total of 6 people and found his place to be very comfortable for all of us. Given that we had 6 we were able to use all of the bedding options and can report that everyone was comfortable and got good night's rest every evening.
Being in downtown Waikiki presents noise issues which are beyond the control of the host but it is no worse than one would expect for a busy city with a vibrant night life.
We appreciated the ample bedding and towels for both bathing and swimming. Additionally chairs, coolers, beach toys and rafts were available for use. You could truly "just show up" and be all set for a fine time at the beach.
As others have noted the building is not nearly as nice as the condo, again not the hosts fault.
We particularly liked the community aspect of staying there in that if you are out of something, just get it (like napkins) and leave the remainder for the next person. There is a high probability that you will make use of some items left behind by prior guests so it is a "pay it forward" type of thing.
Shopping for groceries at WalMart or a grocer is close and there is a 7-11 right next door for last minute or forgotten items.
The Convention Center is about a 6 minute walk from the condo, so if you are in town for something there, this is a perfect location. Ala Moana Mall is just a bit further and going the other direction Hilton Hawai'ian Village and Royal Hawai'ian shopping is a 10-15 minute walk.
We preferred the Fort DeRussy Park Beach which was about a 10 minute walk from the condo. Clean and not very crowded.
Communication with Slavko is as easy as it gets, even in an emergency and the pre-arrival document he provides is quite detailed for whatever needs you may have while staying there.