You may have noticed that during the Convert 3D process in CADmep that your perfectly round solids get turned into something that more resembles a hexagon.
In the process of rebuilding one of my converted items I noticed that my newly converted item didn't look as good as my older one and after a little testing I figured out why. It was the AutoCAD setting "Rendered object smoothness", so I did a little testing and here are my results.
CPU - Intel Core i7-3770K Overclocked to 4.3 GHz
GPU - Nvidia GeForce GTX 680
RAM - 32GB DDR3 1600
Software - AutoCAD 2015, CADmep 2015
Each item was inserted into a blank drawing and arrayed 100x100 (10,000 items) in the model. I then timed how long it took to go from a top view to a front view.
In my opinion the performance was so close that I have no problem setting the Rendered object smoothness to 1. I also tried higher numbers with diminished returns. If you wish you could change this setting while converting solids and switch it back to the default of 0.5 without affecting the items you have already converted. Here is a drawing with the converted items so you can check them out for yourself.