Thanks for your replies - pretty interesting and most pretty damning!
I accept it's not the strongest synthe which is why it has remained leaning up against a wall for the past few years, and while broadly accepting the criticisms levelled at it I have used it over a few evenings and do like its flexibility with three synths per program, and also find its modulation possibilities though D-Beam exciting ( I admit to liking D-beam (please don't ban me from this forum

).
So this GAIA will be used for what its strongest at - bright rich sawtooth based polysynth and pad sounds, swirling noises and realtime LFO control via D-beam - so I'm already finding useful function for it ( FYI I've set it in a new setup with 'left over synths from other setups": a Moog LittlePhatty, an Eminet310, Prophet T8, JD800, CS01 II, Monotribe and Mooferfooger Ring Modulator - all fed into Logic - an eclectic mix so it's going to be interesting to see what comes from it. It might get replaced by a Maxibrute in the next few months
Just to set the record straight - the Oscillator on the GAIA ARE Virtual Analogue. I accept the supersaw may indeed be a PCM sample (and the GAIA does have a GM PCM sample set onboard as it can act totally separately as a GM module - but - Roland strictly separate that function and indeed are at pains to stipulate that PCM samples cannot be fed into the main synth engine. But in any case I can tell the oscillator waveforms are VA).
Finally, the "Envelope" issue flagged is not really an issue - it's a very common difference between analogue and digital synths - namely - for sounds with really long attack and release, a new note (in mono mode especially) will trigger from the start of the attack level with every new note and not from the existing release level of the previous note (as on typical analogue mono synths). So it's not a 'flaw' - it's a difference in implementation ( common on many digital synths - i.e - each triggered note being its own unique entity starting from scratch). So there are no other 'artefacts' with the envelope and as said is a 'feature' noticeable only with rarely used very long attack and release sounds.
cheers,
Kevin