VTL IT-85 New versus Old

I used to use a VTL IT-85 integrated, which I had bought used. I enjoyed it very much, and have thought about trying the latest version. But, given that the older version can be had for less money on the used market, I'm wondering how much the newer version has been improved sonically, or if the changes are primarily cosmetic. Can anyone comment on sonic differences between the older and newer versions? Thanks, and I apologize if this has been discussed in another thread already (I did a quick search, but didn't find anything.)