Weatherby O/U shotguns are made in Japan by SKB. Browning O/Us are made in Japan by Miruko (spelling?). I own both. The Weatherby's sell for much less money,are as good as any Brownings I have encountered. That being said the W guns have a lower resale value in all likelyhood due to less marketing power. Both companys do not have a great record for customer service with the W guns having slightly better than the B guns.
As to the single trigger - double trigger question. Double triggers give a hunter a instant choice of choke as apposed to fumbling for a selector while your flushing bird gets farher and farher away. For the mostpart only some Spanish O/Us sport dbl triggers unless ordered custom fron the maker. Cheers!