Stephen M, it seems like the general consensus is that the Rab Pulse hood is better than the Helium II (though the Helium II's hood has been improved from the Helium I), but the Helium II uses 30D fabric vs the Rab Pulse's 15D fabric.
If all that is correct, that is a tough decision. Slightly tougher or better hood? I've heard several complaints about the hood, but then other reviews make no mention of it at all, so I'm hoping it's just a preference thing.
I wish I had grabbed the Pulse full zip jacket when it was still on sale and available so that I could compare the 2 jackets, but it's looking like I'll be sticking with the Helium II. I don't think I want to bother with the pulse pull-on jacket that's still available- i feel like taking it off will be a pain and get me all wet trying to do so.