spressomon
Expedition Leader
I ordered my Variant sans pad...having experienced the paltry pad with my former Maggiolina...so its just the MegaMat. My pooch stays in the LC...he'd keep me up otherwise 
To protect my knees when climbing in/out I bought one of those mechanic/gardener kneeling pads made from closed cell foam...and its worked perfectly. You could probably carry a couple of them for your dog...many good alternatives that would work too. But the MegaMat is serious comfort! And something that can be aired up easily/quickly with an OBA compressor/tank if need be. I am able to leave mine inflated and along with a down standard size pillow and my Western Mountaineering Sequoia...to just get the top latched down without stressing anything. Since your bag is much colder duty and hence bulkier I would think airing the MegaMat down would give you adequate space for pillow and your -25F bag.
To protect my knees when climbing in/out I bought one of those mechanic/gardener kneeling pads made from closed cell foam...and its worked perfectly. You could probably carry a couple of them for your dog...many good alternatives that would work too. But the MegaMat is serious comfort! And something that can be aired up easily/quickly with an OBA compressor/tank if need be. I am able to leave mine inflated and along with a down standard size pillow and my Western Mountaineering Sequoia...to just get the top latched down without stressing anything. Since your bag is much colder duty and hence bulkier I would think airing the MegaMat down would give you adequate space for pillow and your -25F bag.