I’d have to disagree with not using “quicktime conversion”.
I’ve been doing a lot of web quality exports from Final Cut Pro 6 (H264, AAC) and I’ve found that when I export using the same settings in Compressor I get aliasing issues like that mentioned above.
When I export using quicktime conversion I get a much better result. This is obviously a pain because the quicktime conversion settings don’t stick between restarts. Apple why don’t you fix this!!!
Even though I’ve used it for years and it’s the only way to encode MPEG2, I’m beginning to not trust Compressor.