Lets say you spend $3000 for a multitracker, Tascam maybe. The preamps are good but not great. The recording device will be very good. You still have to spend around $1000 for marginally good mics, another $500 in mic stands and cables.
After maybe a year of learning how to use the compression and effects to match professional CDs you still notice that your not quite getting that top of the line sound you hear from professionally done tracks.
The delta here is the preamps, front end compression and highly expensive microphones pros use, and also equally important is the actual recording space for your drums. This will in fact be your biggest challenge, finding a decent drum room for recording.
In the end you will have spent around $4500, had a lot of fun, learned a ton of things but still not be able to quite produce CD quality. I know all this because my drummer is going through this same process of examination. Here is my opinion on all this.
Get Toontracks Vintage and Custom drum software and pick up a reasonably nice midi drum kit. You will come in at 1/4 to 1/2 the price of the above method. As all of Toontrack drums where recorded with Neve or API preamps, top notch Neumann mics and others, it will sound better than anything you can produce with semi-pro gear. Another thing, you don't have to spend time becoming an engineer and can get immediate, world class results. Last, they recorded their samples in very high scale drum rooms in pro studios.
If you want to make music and get immediate results, a midi tracking drum kit can save an immense amount of time, money and produce much better sound results. Wouldn't you want to have access to multiple drum kits recorded with top quality gear than your single drum set recorded in you garage?
Vintage and Custom - $300
Midi trigger drum kit - $1000
You have the Computer and Sonar, sounds like you are done. Lower cost, high end results.