Some people say that the 105 f/2.8 is actually too sharp for portrait work. Anything can be fixed in post though. Personally, I like the look of the DC lenses and would definitely use the 105 f/2 for that type of work. I think the DC lenses are more kind toward your subject. I have the 135 f/2.
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I have had the 105 VR and now shot with the 135 DC.
It all depends on what type of portrait work you do. Is it studio? Do you use a back drop behind your subject? If you do then I would say go with the 105 VR. In these types of photos you are not taking advantage of the DC effect. If you do outdoor or on location portraits then go with the 105 DC. Once you learn the DC ring there is more control over your photos not just the foreground or background bokeh. Depending on your set up with the DC your subject could be much softer. If you go with the DC route test it with several non-paying subjects first. At different apertures take photos adjusting the DC ring for R and F settings. Understand the differences. For instance photos taken at f/2.8 and DC 0, F2, R2, F5.6 and R5.6 will look very different.
That's a bit of a tough question even though on the surface it should be an easy answer portrait = DC. But the Micro has VR and AF-S along with updated optics materials etc... and with a similar price that doesn't help with a deciding factor either.
I have the older 105 f2.8 D, 135mm f2 DC and 85mm f1.4 G so while not exactly the lenses you're weighing up, a bit of perspective on the FL and general characteristics. I find the bokeh on the 105 D to be harder than the 135 DC, not a surprise, but I'm usually fairly pleased with the overall look with portraits taken with it.
If you're advertising portrait services or they are a strong part of your photography I would say go with the 105 DC because it's going to give those 'wow' results. But if it's just a sometimes thing for you and you like the appeal of macro work then go with the 105 Micro for that and the VR AF-S bells & whistles.