Mga bossing, I have a SmartBro Pocket Wifi 4G-LTE, pls help me decide which Internet Promo should I get :

SurfMax 250 (7 days validity 800mb/day data cap)
Giga Surf 299 (valid for 30 days but only 2GB Shareable data* + 1.1GBfor YouTube, iflix, etc.)
Flexitime 100 (7 days validity but up to 15 hours internet browsing)

My daily activity is mostly browsing for research, facebook, youtube sometimes, etc... I really do not know how to calculate how much mb I need for my internet activities...