We stayed at Vista Waikoloa D-302. The unit was as described in the listing, very comfortable, perfectly clean upon arrival. I slept in the master room, bed was very comfortable and I slept fabulously, rain shower in master bath was really nice! My daughter used the second bedroom, she reported it was very comfortable as well. Great location, 10-15 min. walk from A-bay, King's shops, Queen's market. Unit offered a good value for price, complex was quiet in the evenings, well maintained. Kitchen has all the basics one might want/need/ expect in such a vacation rental.
We never ended up using the pool, always went to the beach to swim, never used the workout facilities either so I can't comment on those.
A couple of minor questions came up during our stay and Resortica staff was prompt and friendly, resolved both questions quickly, no problem. All in all, Resortica appears to run a very professional and well-organized operation, I would be happy to rent from them again.