Well I would guess you are talking to selling dealers as apposed to servicers. And you may only have places that sell and service in your area, but see if you can find an independent servicer only. They won't necessarily have any allegiance to a single brand. If the sell and service, obviously they want you to buy what they sell so they can service it too.
You are considering brands that are kind of odd ball in the main stream. So you aren't going to find much by the way of reviews, hands on experience etc. You may find it better to choose something less obscure for peace of mind's sake, like the wolf etc.
A more common European brand to consider is Miele, they don't sell a freestanding range but they make wonderful ovens and cooktops. Another is Fisher and Paykel, customer service isn't their strong point but most of their products are quite good. They also make DCS, which is a viking/ wolf style product.
Also consider some of the AGA off shoots , such as Heritage and Heartland. You may have better luck finding support, show rooms, etc since these are actually domestic brands that have been bought out by AGA. Although I can vouch that their products haven't been great in the past. Do a google search for the AGA family of products, there are a few other brands that they now own in the americas AFAIK.