I've been experimenting with MP3 encoding for a couple of years now-- quite a bit longer than I've been toying with the DAW. There are as many nuances to encoding MP3's as there are to mixing, it seems. I've give ya what I've picked up so far, maybe it'll save ya some time.
The bit-rate is an important indicator of the quality. The lower the bit-rate, the more information that has to be thrown away to save space, thus lower quality. Different encoders can produce
very different results on the same source material. There are no real "rules" on how encoders decide what bits of the music to keep or throw away. All they have to do is create a stream that any standard decoder (player) can read. Since lower bit-rates must be more aggressive with throwing out information, you'll find the biggest differences among encoders at low bit-rates. As the bit rate goes up, the difference become less noticable. Just because one encoder is really good at some bit-rates, doesn't mean the same algorighms translate well to other bit-rates, either.
All that long-windedness aside... for high-quality encoding, I've been using LAME at 192kbps for a while, but I may switching to using variable bit rate (VBR) encoding with LAME from now on. All techie stuff aside, you get quite a bit better quality for just a little more disk space. In my testing so far, It would be a challenge to tell the difference from my source wavs if I was blindfolded (with a file size just slightly larger than one encoded at 192kbps). I put that in the "good thing" column. Check out
http://www.r3mix.net/ Avoid Xing and BladeEnc at all costs, IMO.
). What encoder are ya using... the highs sound mangled... a bit distorted (listen to the hats), and I don't think it's in your source mix. It's a good feel, I wanna hear more. 
I do think the bass could've used a bit more punch.