Replacement wheels and tyres for 14" Syncros

Following on from Jon's introduction to Metro wheels,
which by the way has an interesting web site and a typically German educational Catalogue for download (35 MB).
I'm interested in what others are doing with regard to tyres and wheels.

I have over the years used two sets of wheels, the original 14" with those fabulous but no longer available Michelin CX tyres.
I also have a set of MBenz 15" wheels which came with Toyo off road tyres, three of which disintegrated in about 50 Ks one hot Christmas in western NSW. To get home I replaced them with a set of Firestone light truck tyres which was all I could get on New years eve out there. The firestones were rugged, and quite good off road, but pretty agricultural.

What are the biggest tyres/wheels, Diameter and rim width, that can be fitted to a standard 14" Syncro ?
What are the biggest tyre profiles, 60 or 70, that have been fitted ?
What tyre brands are Synco owners using with most satisfaction ? I'm especially interested in serious off road tyres.

Looking forward to some thoughts.