Advantage of mastering software

I'm going to try to answer this from my beginner's background. I don't even know about the mastering process when I got started with Sonar - all I do was trying to record and arrange, not even mixing properly.
 
Then, I needed to do some mastering myself - after hearing complaints that my work was not as loud as the commercial one. So I jumped to Ozone / T-Racks for solution - I got two, to find out what are the similarities or differences.
 
Ozone offers many presets to choose from and I get to listen to difference results. I was also learning how to mix properly at this stage. As my mixing got better, I don't have to use Ozone much. I'm using T-Racks more, mainly for some limiting and brick walling process. All these will never be a true mastering work, just a more polished mix.
 
So, looking back, I can now simply use the Pro Channel modules and other effects at the group master to achieve some satisfactory results. However, Ozone / T-Racks play a big role for me to get comfortable to do 'mastering' task without them. ..But I'll still use them for ease use and setup.

I started at Ozone 3 and am currently using Ozone 5 SOMETIMES. I have found that more and more I use the plugs in ProChannel more and Ozone less. Ozone can be quite a bit to deal with and the CPU hit is pretty hard. I found I get probably as good results with less CPU stress using the individual plugs I have in Sonar and ProChannel. BE FOREWARNED! Presets in any plug will be processed over the top so when you hear each preset you will jump out of your chair screaming "WOW! DID YOU HEAR THAT?". Presets should be looked at as starting points to get what You really need for the plug to do. Most mastering when done well is so subtle you will hardly tell a difference other than volume level.
Take some time to research mastering and I would bet that you have pretty much everything you need already in Sonar to get started. I use Sonar X3s tools 95% of the time when mixing and mastering.

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