We had a nice stay at Ocean Vista. While on the outskirts of Mui Ne, the resort itself is fantastic and only a 5 minute cab ride into the heart of the Mui Ne tourist area. It is very well suited for families and big groups.
The pools were great (the Ocean Vista pool is good, but make sure you ask reception for a golf cart to take you to the giant pool towards the north of the property!) and the beach facilities are also quite good. The golf course is a good quality course, but make sure you get out early if it's hot!
The breakfast buffet is quite spectacular and there's probably something that would keep most people happy.
The rooms themselves are quite spacious, especially the 2 & 3 bedroom suites. It was a little disappointing that our kitchen had NO cutlery or crockery whatsoever, other than a couple of glasses, but we didn't cook so it wasn't a big deal. Others in our group had a more complete kitchen, so I think it depends on the specific apartment (they are timeshare style, so up to individual owners I guess). Also, if you're on the backside of the building (golf course/garden view, just be careful when it rains - the balconies can flood a little!).
Overall, I'd definitely classify it as quality western (not just Vietnamese!) 4* stay for a serviced apartment.
PS - most in our group found paying up for beach views worth it!