I assume the hypervent name comes from the frame design that puts a HUGE air vent space between you and the pack.
I looked at the Hypervent but decided to get the Superday. I like it very much but then looked at the Diablo. I liked it online but when I actually saw one up close I didn't care for it. The insides weren't laid out very well IMO. The Hypervent just didn't fit me well.
Either may work very well for you. It's all personal preference. Being able to actually look at and try them on is definitely a plus. My vote for now goes with the Superday.