Those 1-2 gig rips are compressed and the quality is low
The 8-14 gigs are compressed too but the quality is excellent, plus most of those rips have uncompressed DTS audio
You can also download the uncompressed full bluray rips...those are usually anywhere 25-50 gigs but they are full bluray rips(the exact same as the retail blurays you buy at the store)
Yup and you're getting the HD audio with those rips.