For most people who want a polished track that sounds good and doesn't necessarily have to be perfect radio ready, any of the mentioned methods are fine.

With a bit of effort, one can get really nice results from these plugs. I've tried a few of the online ones and wasn't suitably impressed with the results compared to simply using default settings in my plug-in.

I use ozone 10 and have been impressed with the results. Quite often the only changes I make to the final result is to turn off the maximizer module since it seems to really push the output. It has an uncanny way of nailing the genre spot on 99% of the time. Give it a good mix and it'll give you a nice finished product.

I'm still trying to figure out how to get that professional studio mastered sound like I hear from the Nashville hits on the radio but I also realize that they're not popping ozone on the master buss and calling it done. They have mastering engineers in studios with state of the art gear and years of experience. A far cry from my humble in the box studio in the woods and my self taught experience garnered from talking with others about recording, mixing, and mastering/polishing in forums.

Just my 2 cents.

You can find my music at:
www.herbhartley.com
Add nothing that adds nothing to the music.
You can make excuses or you can make progress but not both.

The magic you are looking for is in the work you are avoiding.