Well here it is from the horses mouth:
<<Thank you for contacting Michelin Consumer Care
We write you in regards to your enquiry about Michelin Agilis Camping tyres on your Roller Team Pegaso motorhome. We have checked this question with our technical department, and they notified us that, as you already know, in Germany cold weather tyres (tyres with winter certification 3PMSF) are obligatory for all users, according to climatic and driving conditions.
As for Austria, tyres with the M+S certificate are mandatory. The M+S (Mud and Snow) certification indicates that the tyres are designed for mud and snow (in winter) conditions. Unlike 3PMSF (three peak mountain and snowflake) M+S certifications have not been subjected to standardised testing. Furthermore, in Austria, it is mandatory to have more than 4 mm of tread depth remaining in the tyres that are currently mounted on the vehicle.
As for Switzerland, it is not mandatory to equip winter tyres, however you are responsible for having the necessary skills to drive safely under winter conditions. We strongly recommend to always carry snow chains, just in case. In Italy, especially in the northern part of the country, it is strongly recommended to have tyres with M+S certificate, and always carry snow chains on board.
As for availability of our tyres, in size 225/75 R16 we do have available both the MICHELIN Agilis Camping and the Agilis CrossClimate. Given that you mentioned that your motorhome has a total weight of 3.5 tones, both of these models would be suitable for your vehicle, as they can carry 2640kg per axle, which makes a total of 5280kg of bearable load. Still, we recommend to check the manufacturer's instructions as for speed index. These models have a maximum speed index of "R" which means that the tyre can reach a maximum speed of 105 miles per hour. You can also check the manufacturer's recommendations in the technical guide of your vehicle.
Nonetheless, since it is a motorhome, the only recommendation I could give is to mount the Agilis Camping, because this tyre is exclusively made for motorhomes. Its robust design is designed to withstand wear and damage associated with the heavy load campers. It can withstand long periods of no movement (being parked) without suffering tyre deformation.
The Agilis Camping is a summer only tyre, but has the M+S certificate, however it would not be legal to drive in countries where winter tyres are mandatory (Germany, Austria). You would have to mount the Agilis CrossClimate in order to comply with these countries' laws. However, as I mentioned, the only official recommendation we can give as for motorhomes, is the Agilis Camping. We strongly recommend to seek advice with the vehicle's manufacturer to see all the options you have as per which tyres to mount.>>
Following up with the manufacturer of the motorhome... They neither recommend or advise against the use of tyres not fitted by themselves, they say it is up to the owner to satisfy himself that the tyres chosen are suitable. Michelin say the tyres are suitable for a 3.5 ton motorhome, both are well aware of the need for certified winter tyres in Germany and certified M+S tyres in Austria, but to avoid liability both prefer to close their eyes and shrink away from making any recommendation on the subject. Michelin say the advantage of the camper tyres is resistance to deformation from long term parking. Since we use the van regularly all year round I can say am reasonably satisfied they are suitable as it would appear are the numerous van owners driving round the Alps with Agilis Crossclimate tyres. Indeed if one used the camper tyres in winter in Germany one could be prosecuted and have
insurance voided because they are not compliant with the 3PMS certification that is required.
It’s what it had on when I bought it so I replaced 2 like for like about a year ago and I need the other 2 replacing this mot.