My wife and I tested the Diplomat today and will give our impressions.
Pros: You can run all jets at the same time with good power. My wife has bad circulation in one leg and foot, so she is looking for therapy to those areas. She is also 5' with short legs, so it's hard to fit her properly in most spas we have tried. She liked the longest ultralounger as the calf jets hit her feet. I thought the hydrotherapy seat was okay. The controls are very easy to use and the audio system is awesome, the two speakers just plug into the top side of the spa and our Cd's sounded great.
Cons: The diverters are behind your shoulder when lying in the loungers and are hard to adjust from that position. I'm 5' 9" and I didn't fit properly in either of the loungers. My wife floated in both loungers, may need to put a weight belt on her if they make them for that purpose.
This is the 4th spa that we have tested, the others are the vista, envoy, and epic with the envoy still being our favorite so far.
Ron