I never experienced the offerings from Daf but I know some that thought they were a good thing, all that glass looked cold and not very inviting, but I never realized it was double glazed. Like wise the Big Transcon looked like it would suffer from the same circumstance, as did many trucks from that era. If I remember right Marathon was the same, as were Volvo F88 F86, Merc, MAN and Fiat, all suffering form the gold fish bowl look, Again probably down to the fact that the trucks were being designed by people that had little knowledge or interest in trucks, other then being a stepping stone from them to get into car design.
I realize that when sleeper cabs first came out there would have to be many compromises between what could be done with out causing to many structural changes, added weight, as well as what size could be obtained with out to much physical and or optical impact. However I think a lot of the earlier problems could have been solved if at the design point if there had been some kind of input from drivers, and not just a bunch of designer that had some quirky ideas.
First problem would have been comfort, and practicality, I’m not talking about excessive luxury, with expensive fabrics, but basic design and requirements were sometimes overlooked by people that had never experienced what it was like to actually drive a truck let alone spend long periods of time in one. Some designer took that to the extreme where it seemed that every part was as cheap and minimal as possible then reduce it by half again. Thin bunks made from nothing more than ply and foam didn’t do much for a good nights sleep as did the lack of insulation, and many drivers on various threads have commented that half a board over the engine hump was a better option than a factory sleeper of the same time.
How many trucks were actually double manned? I don’t have any figures for that, but when I was driving around I very rarely saw any trucks that were, however many trucks had 2 bunks crammed in where one bunk with a bit of thought out clever space would have been a far better option.
There were rare occasions where wife’s, girlfriends, boyfriends, and or kids went along for the ride, but for most trucks most of the time it was one driver on his own in the cab.
I would assume that if you asked 100 drivers what they wanted then you would get 100 different answers but there would surly be some kind of common ground, like good curtains that actually had some insulation value and kept the light out during the day would actually be a good thing. If you were paying big money for a truck then surely a bit of extra money at base for things like that would go a long way for the reputation of the manufacturer. Unfortunately it’s small things like that that can make the difference between people thinking you have a good product and thinking your a tight a##@# cheap skate.
Two of the better test that came along in later years were the trousers on test, IE can you stand up in the passenger foot well and get dressed. and can you sit up in bed with out hitting you head on the roof lining. Both these thing might seem trivial to designers and bosses but when you spend more than half your life living in an 8 foot cube tin box it becomes very important.
I also remember one magazine testing for insulation where the night heater and switched of and the temperature was monitored through out the night, which I though was a great test. It turned out that between a Volvo, Scania, Daf, and Magnum the Magnum was worse by a very long way.
Interior lighting in most sleeper cabs was woefully inadequate and poorly placed, Yes it comes down to a compromise between various factors, but what’s a bit of wire and a decent light fitting at the design stage.
Don’t think I’m not great full for what I had because I am and after many years of crashing over the seat of various Fords where at one point I was considering getting a tent then anything was better.
After many years of living in various sizes of tin boxes on 5 continents I have my favorites, but at the end of the day I have to say that even the biggest of American trucks with camper van size sleeper pods get very small after a couple of weeks pounding the black top.
Jeff…
,cause a tear or two to drip into “Saviems” Lambrussco this evening 
IMO the Magnum was the finest sleeper cab produced to date when I took this photo in '94 at our site in Kendal,they were both coupled to Grahams of Gildersome 4 mtr curtainsiders.Bewick.
