I faced the same issues and honestly I was wondering why only so few people were bothered by it. The problem is that the driver support for the MediaTek 7621/7615 chipset is bad in FW 3.201 (as you can see from the fact that LuCi does not work properly), the country settings are not appropriate (and, even worse, not configurable via GUI) and that DFS is obviously not working. See my other post for a workaround. MT1300 (Beryl), FW 3.201 and DFS. I am still thinking about returning my Beryl and getting the slate.