Difference between mini and hd units?

Hey Guys,

I am looking at buying a unit soon. Can everyone give me there opinions on the two units.

I will mainly be downloading torrents and would like to just watch them in AVI files so I can stop converting then burning them!!

I will be watching them on a 1080i plasma.   Any suggestions would be great

THANKS.

Do not buy the WD TV Mini as it cannot play MKV file which is very important for high-definition and high-definition RMVB file also cannot play. I regretted it 10 minutes after buying the mini.