So my usual pseudo-mastering is to just get the volume up to an acceptable level for all my tracks, so I throw a master limiter on the rendered stereo track - with it set so it barely compresses the very loudest parts of the sound, and then a compressor after to just boost it up 0.1dB (a trick someone here posted). Generally happy with the results - I try to get the mixes right, so no correction is really needed. Once I've done this to all the tracks for an album release, I listen to them all on different systems to adjust any volume or tone inconsistencies.
I had downloaded the free Ozone 8 Elements ages ago, and thought I'd give it a go for the fun of it. A song I had just used my mastering on, and was happy with the results - mostly acoustic guitars, bass, violin and vocals. I disabled the plug-ins I had on it, put Ozone 8 on, and clicked the 'assistance' thing. OMG! Horrible clipping/distortion. I don't even know how it could do that! I disabled that, tried a few of the presets, none of which boosted the volume up, they may have changed the overall EQ or stereo image a bit.
I'm going to try it on an electric/band-type mix to see what happens.