Apologies if this has been asked before (I'm sure it has but can't find a specific answer).
I'm thinking of taking the CS back to Glasgow, getting in the morning, and going to work that day. I'm not sure I want to splash £200 on a bed, but the seated option looks good value. Is it actually comfortable enough to sleep in? Some previous comments refer to it being too cold which is music to my ears (can always put on an extra layer, and hot weather is nightmare for me). The seats recline 10 degrees, which doesn't sound like a lot to me, but still sounds better than the Avanti ones!
Well it depends on your definition of comfortable!
I cannot sleep well sat upright at all. Even if you gave me some memory foam seat, I wouldn't sleep well sat upright.
I have however taken a lot of overnight transport where I've had to sleep upright.
I find the CS seats perfectly comfortable. I too find heat much worse than cold, especially when sleeping. You can always take a blanket or sleeping bag, but you can't cool down when it's too hot really. The recline isn't much, but frankly it isn't on any train or plane unless it's going to fold down into a bed. The seats themselves are comfy enough with headrests etc.
One thing I would point out is that nothing really stops you sleeping on the floor. Because I can't sleep well upright, I got into the habit of waiting until the final pickup point had passed, then going to sleep in the corner in the wheelchair area. I used to take it for hiking trips so I often had a sleeping bag which helped, but I sleep fine pretty much anywhere as long as I'm lying down not sat upright. Nobody will care, even staff, and almost everybody will be asleep anyway so who cares.