Element-
If looking at the Trinity or Triton- invest the extra in the 6 voice MOSS board. This has got mega fantastic analogue synthe sounds that would blow away the sampled based EX5 analogue emulations (and the sampled Trinity or Triton emulations also of course!!). Yes the Korg's and Yamaha's have a very different sound that's for sure!!!!
The Yamaha has a bad timing response period. A couple of the magazines reviewing this board all complained about it and I'm not sure whether Yamaha did anything about it or not. It might even be worth finding out whether they may have upgraded the processor or something like that to improve the timing!
Fact is that the EX5 is a more powerful 'synthe' than the Trinity or Triton. But the Triton has a better sampler and there are no loss of effects when using DSP voices etc.
I've not heard of a new 128 voice Korg instrument- but of course they'll bring something out to compete with the other manufacturers- if not this year than next year for sure!!!!. I do not see the point in waiting for technology to 'catch up' because you will be waiting for ever!!!!!!!!!
However, if you have any info about the new Korg synthe please let me know. Thanks.