I started out using music match 4 @ 160kbps, but soon I was able to pick out the glitches. I upped it to 192Kbps but still I could eventually hear the artifacts.

After some research I learned that not only is it the bitrate that matters, but the encoder itself matters. Some encoders do a better job than other with the same number of bits.

I've since settled on EAC + LAME (started at ver 3.87) and slowly but steadily re-encoded my whole library. After extended listening, I'm really pleased with the sound quality, and would recommend VBR over CBR, as there are just some parts of music (usually the most complex and sonically interesting) that need the extra data encoded.