As for FUP - its become a daily part and parcel of life - after all when you are going for unlimited food - there too its served slowly after you 'download' too much
It's Possible for them to Offer unlimited plan. But Technically Its not possible for that price and that Much amount of Gb's. fivenet has also earlier offered "up to 10mbps Unlimited"
They would assume Customer would download heavily in the initial months and later slow down his pace assuming. Right now i don't See they allow you to download as much as you can download on Fivenet. They peer with NIXI that tells the story in Short a silent FUP is applicable.