Right- it's a pretty standard issue with testing processing software. There are several approaches, but the "default" approach gives you at the very least an understanding of where the manufacturer puts you as a starting point, and how the camera files are treated. If that default method brings you closer to where you want to be at the outset, you have less work to do.
If you were to try to compare two packages at "best advantage", it turns very quickly into a bottomless pit of subjective issues and processing methods. Not only does it become a skill-dependent issue, but it also becomes an ideological debate (for lack of a better word) as well- you could easily, for example, point at my preferred method of gray balancing, (or sharpening), and find issue with that, based on your overall processing strategy.
To put it differently, it would be a really interesting review to take two files from two "masters" of their processors- people who know the software and how to get the most out of it and then compare the files. Even that, though, you can see is a tough situation to make conclusions about since what you will really be testing is their tastes and preferences in how a file should be processed, not what each processor does and why...