Questions Regarding MPEG2 Reencoding in DMF3

[steeleye]

1. How much quality degradation occurs when reencoding MPEG2 in DMF3, assuming all parameters are the same between the inital capture (with ATI MMC in my case) and reencoding (resolution, VBR, average bit rate, etc)?

2) If I have to reencode in DMF3 because of audio sync problems when "do not reencode compliant file" box is checked, is it better to initally capture analog material in MPEG2 with I-frames only or possibly AVI?

3) Why are the file sizes output from DMF3 substanitally larger when allowing DMF3 to reencode an MPEG2 (with the same parameters that were used in the initial capture) compared to when the "do not reencode" box is checked?