It also depend I think on what kind of music you do...
I have a Motf ES rack at the moment and a Fusion. My use for a workstation is really down to a need for a decent piano-like weighted keyboard and stock rompler sounds and a useable piano thats is not going to sound like hell when heavily processed - think housey dance music, but alot of ambient/chill stuff as well.
Sequencer etc - Im not fussed about to be honest, unless it is trivially easy to use - otherwise Ill use a computer. If its simple and quick and allmost transparent use then ill use it for quickly capturing stuff for jamming session when a computer is too much of a pain to mess with.
So nothing about the Motif XS exactly screemed flog the fusion and es rack and get one... Im sure it sounds better - but who cares - Im not a jazzer, and TBH - the yamaha sound on the motif es has never really grown on me though there are some excellent sounds in there.
As for the fusion, well - I really liked that to start with to play, but mixing with its pianos is a pain - I tend to run alot of compression, reverb, delays etc and that just seems to bring out every nasty artifcat in the fusions pianos, so I use the Motif ES pianos mostly along with loads of its pads and otehr noises ive programmed on it for layering acroos other synths for pads etc - typically the kind of stuff that needs a sample as a base - glassy vox etc... Its arps are cool, but dont really use many of them. Its performance mode is alot of fun, its fx are well... crap is the word that comes to mind (I have a fireworx, so no contest really).
The XS as a sound engine would therefore have to do something very significant to grab me. Is fookin ugly too and nothing much grabs me as a practical reason for it to be so big and ugly.
Fusion - excellent organs, wurlys etc - not that I use them that much. Sounds are very raw very fun to play. Loads of very varied sounds in it. - but I dont use much of them. Its VA is quite decent, as is its FM blah blah... fx decent too. Its brutal sample switching sux - urrrgh!
So why the M3? Well - korg workstation sounds seem to suit electronic music better than roland and yamaha to my taste, I allready have a radias-r - sticking that thing that thing next to the M3 module would be a great workflow improvement.
And of course the karma engine - for background stuff - that just saves so much programming - its what I like about the radias too - its a great synth for creating lots of interesting background texture to your music.
X/Y pad on the display is cool too - im a huge fan of X/Y controllers - Remote 25, V-Synth and a KP3 here
If the sounds are good, the sample switching isnt bad and of course the price is sensible, then yeh - I can very easily see myself sending the Fusion 8HD and Motif ES rack to ebay for an M3-88 - one less synth to worry about is nice too. I just think the end result will make a completely wicked performance combo that no other workstation can match if you consider the benefits of having your companion synth panel there as well. I like tilt up screens to, and the touch screen - you know - this thing just seems *right* like someone sat down and gave the end user some thought for once...
So long as the sound is on a par wioth the others, then having a good easy to use performance machine can be way more useful than the best sound engine behind some hideous UI - and you never - this thing might actually sound good next to the others as well.
** Hideous UI refers to early Yamaha oferings - the XS may actually be better... ...nah - then it wouldnt be yamaha...
