I find it very strange that nobody has either one of those tents on here. Remind me what forum this is? I may as well have posted this on a gardening forum I probably would have had more response there might be room in it's porch for growing cabbages. I put that down to kit snobbery because it's a Vango. It can't just be down to price either because the Zephros tents are very popular. Very odd.
If anyone has got either of these I'd be interested on your opinions, and if used in anger in some Scottish weather all the better. The only thing that's off putting with the Helix is it's seemingly low height. I don't like sitting hunched with my head pressed up against the inner same as in my Zephyros (I'm about 5' 10"). Whereas the Zenith is a bit higher (also the heavier of the two). Both of these designs have their advantages & disadvantages.
The main thing I want to know is whether there's enough room for cooking. The Helix doesn't seem to have a porch as such but I assume the inner at the front can be unpegged and pulled back to make enough room for cooking? I'm not sure there's enough space in the Zenith without doing the same, more difficulty in pulling the inner front/side back with that design but that's what I do with the Zephyros but it is a bit of a pain.
Water resistant isn't the same as waterproof. Water resistant gloves are the way to go though let them get wet and dry fast, they only need to keep your hands warm which they will do even if they're wet. It's not even cold in June except night time or you're up high up a mountain. Waterproof gloves get wet and stay wet especially sealskinz ones you'll have try and turn them inside out to dry them which isn't easy. As Peter said water runs down your arms and in and one other way I'd get them wet is when taking them off to take photos or to use my phone or something when it's raining, then I'm putting my wet hands back in them. Sealskinz socks are good I wouldn't touch their gloves again though, the pair I had leaked as well (fill them from a tap to see if they leak). If you're trying to stop stuff getting wet in Scotland good luck with that.
Pegs are quite bulky? Blimey how many do you need? I think I take 4 (without checking) along with some paracord. Tops you can tie the arms (wrist ends) together and trousers the ankle ends. You don't even need to use cordage if you don't want to you can wrap them / tie them to a tree. If you're camping near trees that is instead of having to use a trekking pole and the end of something else / your tent. I only take one trekking pole along.