I had this problem quite often that I needed to rescale a model and after doing so was left with a smoothed out model that lost all detail. in the past I would either export the low base to 3dsmax, rescale and re-import, or scale it with transposer master. today I had to rescale a body with teeth by 300% and eyes subtools.tried it with transposer master and since that resulted only in detail loss again, I just gave it a try with GoZbrush into 3dsmax and back.
To my surprise it worked flawlessly. no detail lost at all. 