Hello folks...
feefer the URL you wrote is just an alias of what i wrote.
Nate_Straight i have XV88 and one 5080 on my desk. For more information read older posts in this forum. I've posted much of them so you can search or browse and read about XV88.
BTW XV is far better than Yamaha S80 although S80 is also excellent value. XV88 feel is exactly piano weighted and somehow better than S80's feel. The real case is if you need the Roland or Yamaha sound. Synth engine in two keyboards is similar but Roland always had deeper synthesis with much more control on various parameters. Take a look for example in matrix mod, cross mod, insertion FX etc.
As stigf says S&S means sample & synhesis. The S&S synths are just playback samplers using internal or plugin sample waveforms and many modulations editing options to shape the sound but not the samples themselves. Most of current synths are S&S and they differ in editing method, algorithms, FXs, and quality of internal samples. These are where Roland XVs shine.