Would like to get an idea of how this differs from the Eolus so I can make a purchase decision or wait.
From what I've read...
The Eolus and Guardian are both 2-person shelters.
The Silex can pitch to the ground, or off the ground for more ventilation, but the Eolus can only be pitched off the ground, so the Eolus always has ventilation around the perimeter.
Maximum ventilation would be better for hot weather and/or controlling condensation, but not so good for windy or cold weather conditions.
The Silex can come with a stove jack, the Eolus cannot.
The original post in this thread described the Guardian as the big brother to the Silex, and that the Guardian can be used as a hot tent.
So, I think the main differences between the Eolus and Guardian 2-person shelters are that the Guardian will be able to be pitched to the ground and have a stove jack, while the Eolus has neither of these capabilities.
The Guardian is also supposed to have doors that open a little higher than the Eolus, similar in design to the Silex, so the Guardian should be a little easier to enter than the Eolus.
If you're only using the shelter in warm/hot weather, you could get the Eolus. But, that doesn't necessarily make it better than the Guardian in hot weather, because although the Guardian can be pitch to the ground, I'm assuming the Guardian can also be pitched off the ground (like the Silex can be) giving it perimeter ventilation like the Eolus. And, you can always also open the Guardian's doors as little or as much as you'd like, for as much ventilation as you'd like.
If you want to pitch your shelter to the ground, use the shelter in colder weather, and/or use a stove, get the Guardian.
Personally, I wonder if the Eolus will become obsolete once the Guardian is released because they're the same size and the Guardian just seems like a more versatile shelter.