I'm not sure exactly how much XP you get in total, but it's well over 100, maybe around 150. I'm not sure why they went with triffids, as it's not very well known in the US, but Day of the Triffids is very well known in the UK.
Personally, I'd have gone with Killer Tomatos.
I have never made but one prayer to God, a very short one: "O Lord, make my enemies ridiculous." And God granted it. - Voltaire