I've got
a VS840Ex. Why do I use it? Because it DOES have everything in one box! I must admit I do use my computer for MIDI and mastering and that is because I can't play the drums, and recording a full string section is just too much to do with real musicians. When using it to master my mix, not much has to be done (a majority is already done on my 840). All my editing and mixing is done on my 840.
One distinct advantage over a computer with a workstation is that you actually have faders that you can play with (instead of moving just one at a time on the computer.
As for plug-in's in the workstation, for a gutarist, it contains all the BOSS pedal effects, which are all tweakable. It also contains mic sims etc which can all be mixed together.
I do know that some people use out-board effects because some effects or processors aren't up to scratch on the 840, such as the compressors which everyone seem to talk about in the lack of quality of them.
I guess it's strokes for folkes. I was finding that in front of a computer I was losing my creative flare. I used to do a lot more MIDI on my recordings last year than I do this year and that's because I want to be acoustic in my songs. I used to always have a MIDI bass. To make my recordings sound better I went and bought myself a Bass Guitar.
The ability to record anywhere anytime is a great advantage. I recorded a sperformance of a song which I wrote at my engagement party. I couldn't see myself taking my 'hi-tower', monitor, keyboard, mouse and a mixing desk along to record it there, I just took along my workstation!!
Anyway, I've got to get back to work... just have to give my point of view.
Porter