I currently use Thermarest Neoair.
These depend on internal baffles to prevent convection rather than down, and there's nothing inside that's going to suffer badly from damp, so inflation by mouth is possible.
The light weight version (Xlite) is similar to a light self-inflating mat with a punched foam core, good down to 0 to +5 deg C.
The warmer version (XTherm) is similar to the Downmat 7 in warmth.
Thickness is the same as Exped (7cm).
The baffles run crossways rather than longways, so some people may find they fall off the edge more easily, but there are also wider 25" versions as well as the standard 20".
A short Xlite rolls up to the
same size as a water bottle, the full length XTherm is maybe 75% fatter when rolled.
I've not had any failed baffles in the 5 years or so I've been using them.
If you want tough and reliable, closed cell foam mats like the original Karrimat are where it's at. The penalty for reliability is bulk and comparative lack of comfort.
Self-inflating mats:
A 2.5 cm mat is OK if you sleep on your back or front, but side sleepers may put a hip down onto the ground if the mat isn't fairly firm. Thicker are OK.
If the foam core is punched full of holes (for lightness), the mat isn't as warm, so a 2.5 cm mat may only be good down to +5C.
A 2.5 cm unperforated core mat is OK down to maybe -8C.
They can delaminate, which is the equivalent of the failed baffle. You get a big bubble where the shell is no longer bonded to the foam core, all the air goes into the bubble, and you go down onto the ground. Because the shell meets the foam core at an angle at the edge of the bubble, the bubble grows very easily.
I've had two cheap & cheerful self-inflating mats delaminate after very little use, and one pukka Thermarest when left inflated hard inside a closed tent on a sunny afternoon in Briancon whilst we looked for a replacement set of forks for my mate's bike.
All temperature judgements are for me. YMMV