ok, I'm now officially intrigued by this issue.
If anyone out there is an expert on Roland sounds or sound design in general and can clear the fog, I'd like to know the following:

There are similar patches on the JV-2080, XP-30, XV-3080 and XV-5080, as well as the colossal XV-88.
By 'similar', I mean the same factory preset, same name, etc. Now, could it be that this same preset sounds entirely different on different Roland synths/modules?

For example, I was at Sam Ash yesterday tinkering on the XV-88 and pulled up a bank of patches I'm familiar with, ones I have on my XP-30. Taking a patch like the "Trem Rhodes", it sounded much, much better on the XV-88 than on my synth.
Same with any other patch that I was familiar with, even down to the drum kits. In a nutshell, they just sounded fuller, richer, warmer, all that jazz.

So, could it be that although you'll find the same presets on various Roland machines, an XV sound engine compared to a JV or XP-30 will sound that much better?
This brings me back to my friend's thoughts on the XP-30 and it's 1200+ sounds, which he says are so heavily compressed in order to fit more on the machine, they lose a lot of dynamics, hence my observation of a cold and sterile sound.

Any comments on this are greatly appreciated...

pk