Another Bill White Ins. customer here. Started with them when I bought my Supercub a couple years ago. At first, the underwriter wanted 2 hours dual in a supercub before they would insure me with about an hour logged in super cubs, but I convinced them to consider recent experience in a Rans S-7 as a similar type (where would you go to get 2 hours dual in a Supercub anyways

), as my cub was getting the engine rebuilt, and wasn't about to spend the first 2 hours on a rebuilt engine doing touch-and-go's. As it turned out, it wouldn't have mattered as the rebuilt engine only lasted 29 hours, but thats another story.
Now I insure my Skywagon with them. First year was about $1400 for a $75,000 hull value. Second year they quoted the same price, but I called and asked for a discount for 100+ hours in type, and they obliged and got the premium down to $1228. I'm happy with that...
The actual underwriter I can't recall (no big name), but there are no exclusions, and good for Alaska/Canada too.