Hmmm.
I own an Emu 6400. This was after months of looking at Kurweil, Triton, EX5 and XV88.
Why the Emu? Its probably the best all around sampler today. It also kicks the living crap out of the others for brass, strings, piano and other "authentic" instruments.
I felt the Triton still sounded hollow and synthy in comparison to the Emu...and while a lot of bands use the Triton as part of their arsenal - advertisements and film scores are done with samplers...because there aren't a lot of cymbals and drum kicks to mask some of the weaknesses.
As far as the PC88...what is that going to serve? Is it basically a MIDI controller? That's a wad of cash to drop on a MIDI controller - especially when you can get a dedicated MC.
I'm betting you can get pretty close in price with:
Fatar Hammer Action controller (I have Oberheim MC3000 - and feel its a little superior to the Fatar, but harder to find in a store)
Emu 6400 - upgrade to 128 MB ram and get a large IDE hard disk (Advantage over the 5000 is its got better upgrade paths and comes with a load of decent samples)
Triton Rack - if you can afford it...and definitely the MOSS. This gives you great analog synth sounds.