I thought ToddTex was distinct from Goretex?
I have several tents in this design (original Bibler, North Face and Black Diamond) and use them for both summer and winter travel. I think it's a great design. A friend of mine also has several and swears by them.
Last winter ski trip:
That tent opens on the side but otherwise it's the same single-wall, internal two-pole design. It's very roomy for it's size and small footprint. My wife and I did a 3 week backpack trip with that tent. It's our first choice for summer backpacking in California (not in Tasmania).
The lack of a vestibule can be an issue sometimes. Although it is possible to simply close it up for cooking it can be problematic getting in and out if there is precipitation. In California that's less of an issue but it can still be a problem.
On some trips we take a clip-on vestibule. You can buy them for the Black Diamond/Bibler tents but they're kind of overkill. I sewed my own and it weighs ~200g. Here's a shot I took of it (opened up so it's kind of slack) when I got out one night for a pee during a late season hail/snow storm:
The original Black Diamond Firstlight (circa 2007?) weighed about 1500g so a 900g tent is a big weight savings. Durability of the Cuben is of course a question. The original Epic fabric of the Firstlight (and Lighthouse tent in the photo above) had some detractors. BD has since switched to the somewhat heavier NanoShield fabric) but we've had no issues with our tent. But it is obviously fragile and requires some care. I would suspect that a Cuben tent would be fragile as well -- maybe more so?
It's part of the current trend though: lighter, more expensive and shorter product life.