So, I had a stratospire 2….and set it up and started trying to fit 3 full length pads. After all…tarptent says its a 2-3 person tent. It even says on the site ->
Q: Can I really use this for three?
A: Yes. The interior will widen to fit three standard width sleeping pads. The standalone fly will easily sleep three.
I wish I took pictures of my attempts. I mean, tarptent does show pictures of the mesh inner with 3 pads in it ->

From my recollection…this was not possible to do. The area between the two poles at that angle is enough for 2 pads…not 3. In that picture you can see the 3rd pad up at an angle…b/c its hitting the trekking pole. If I remember….I tried getting 3 pads at that angle, but I had to angle the trekking poles and they were too steep. I wouldn't be comfortable sleeping under any conditions with them at that angle…let alone a tiny bump would have knocked them over.
On the other hand, they have this picture if you pitched the mesh only ->

….which…yes, would be extremely tight with 3 humans inside it since you would have to ensure that each human stayed in their 20" of designated width. But…could be possible.
I believe it was possible to get 3 full length pads without the mesh inner under the fly situated more or less like this picture from franco ->

You have to angle the pads between the two poles at odd angles, but it was possible with 3…still…kind of odd but possible with no gear. Now that picture with 4 is where I had difficulty with…I could NOT get 4 full length pads situated under the fly in any configuration. As you see the yellow pad in the picture….I myself could not get the 4th full length pad in that spot without it sticking out the backside of the tarp a couple of inches. It was on the tarptent site, so I was discouraged that I was not able to duplicate what they had in the pictures.
Which …I think the stratospire 2 is a very cool design…but its for 2. A luxurious 2…with 2 large vestibules, but 3 is quite clumsy.
Franco frequents the boards so maybe he has some input on this, but me personally…I wasn't able to replicate the pictures.
I thus sold it for a supermid. Supermid is under 25 oz without guyline or seam sealer and takes roughly the same footprint as a stratospire, but since its square will definitely accommodate 3 comfortably with gear….or 4 tightly.