their faqs are pretty detailed. 99% of songs are available in 320kbps. by default it would download 128kbps versions. though you can specifically ask to download the higher quality version. only four downloads per songs are available. did you use their download manager?
Apple itunes i believe requires you to authenticate your computer to download your song tracks. you have to deauthorize a machine before you can authorize another one. i think they do allow 3 machines connected to a single account. hard to say.
the fact remains, the limitations are being enforced by the music labels. Flipkart is bound by the terms and conditions.
Google Music has similar restrictions. You can download your songs from the website only two times. But you do get the ability to download tracks on an authorized machine using the Google Music Manager. Though they do not allow single downloads through the desktop app. You have to download your entire library.