Hello,
I read your posting and decided to add my two cents on this subject. I used two units in my studio for the most of stuff I make - one is a synth and another is sampler remix workstation and it worked very well!
In this case, I had the best of both worlds - any audio loops that I like and the anolog-like synthesis for everything else. Now I am moving up, I got some cash from the tracks I've made, and I am selling my Roland SP-808PRO Sampling Workstation, switching to a bigger sampler. I don't write it, that you will buy it from me :-), but rather to give you an idea, that this type of setup is working great! I also use Roland JP-8000 - boy, I love this machine! These days, it is very handy to have some type of sampler - it gives you much wider range of sounds and drum loops etc. In combination with a good synth it works perfect!
Anyway, just a thought...
-r-