First off...screw the "mastering software", and get a proper interface and get the tracking part right. Second of all, why are you so intent on getting tracks to "commercial levels"? Over 90% of the time it sounds like crap. And as far as the radio...the already squashed CDs are getting a couple extra layers of squashing.
There's something wrong if you're tracks are so quiet that you can't hear them. It's possible to get tracks at a respectable level without being squashed to death. Trust me, if the track is hot, there's not a soul that matters who's going to care if it's not quite as loud as the "toddler" track. 'Cause if it isn't...then simply turn up the volume.
But you know what DJ Echo...therein lies the problem with today's home studio revolution. Back in the day, not everybody with a home setup expected to churn out "radio-ready" recordings. And even those that did have pretty decent setups still involved other people. We live in a world where not only does everybody want to wear all the hats, but just about all of them think the hats fit perfectly. Recognize shortcomings and be willing to pay to get it right. There's no such thing as "no money to do it" especially when a gang of people are involved with it. Fifty bucks a person is $200 if just four people are involved. Add in a little more and you may not get Massive to do it, but you can find someone around to at least have your mixtape ready enough for the world. 'Cause the bottom line is, there's squashing by people who know what they're doing and squashing by people who don't. And if you screw it up, your current project may place a sticker on every thing else you release that says "this will sound like King Kong stepped on it". So my advice is, do what's best for the project, Neal. No compromise. Paying for better ears to record and/or mix, and especially master is ALWAYS worth it.
Oh, and BTW Morning Star...you're going to have to school me 'cause I've never heard of a sound card actually making your computer run "MUCH MUCH faster". I am certainly no computer expert, so fell free to elaborate. Thanks.
Peace