The dates of departure and arrival were so close that a race is suggested, whereas other factors, involving the different departure ports, Whampoa and Shanghai, and the fact that the deep-drafted American had to wait three da ysin London for enough water to dock, rule this out. The American clipper Nightingale is also involved in the controversy, having left Shanghai three days after the Challenger and having conflicting dates, before and after, for arrival at Deal. During the following year, 1853, both the Nightingale and the Challenger left Woosung together, and the Challenger arrived two days ahead at Deal. Another American clipper, also called Challenger, was built in East Boston in 1853 and made a passage with tea in 1856 from China to London.
The American clippers in the 1850s outnumbered the handful of fast British clippers and took the best of the tea crop for some years, although individually some of them were well matched, the honours being about equal on both sides.

   Unfortunately more incidents occurred with the Chinese authorities, and their seizure of a ship carrying the Union Jack under disputed circumstances brought on another war in 1856 during which Canton was blockaded and shelled, although some trade was still carried on with other ports, officials less patriotic than Lin being desirous of profits from opium.
The treaty of Tientsin, concluded in 1858, opened up inland ports such as Hankow to the British and French and legalized the trade in opium on a limited scale. The East India Company was dissolved the same year, the pressure from other shipowners finally being effective.

   A commercial treaty was also made with the United States, although by 1860 their clippers had withdrawn from the British trade, the Flying Cloud being the last ship to arrive in London with tea. Some of them continued carrying tea to New York for the next three years, and it is said that two old-timers, the barque Maury (later renamed Benefactor) and the Golden State, were able to pick up a tea cargo for New York each year until 1875.

   It is interesting to note that in 1858 two American cli ppers, the Panama and the Picayune, lying at Hong Kong and trading to the United States, were said to have had black crews, the former ship with the exception of the officers being entirely manned by them. But for the majority of the American vessels hard driving had made their upkeep costly, and bad economic conditions at home, with an increasing lack of enthusiasm, forced their withdrawal. Their life was not over , however, and under reduced rig many of them did good work in other trades under the British and Dutch flags.

The race to bring fresh teas home was now between rival British owners, and the trade reached its peak with the composite clippers of the 1860s. Steamships up to this period had not constituted areal threat to sailing clippers on long voyages like the China run, owing to their need to  refuel frequently at coaling stations off a direct route.