While bankers see big benefits from Qianhai development there is scepticism elsewhere in the financial industry about whether the plan will benefit the sector or the Hong Kong economy as a whole.
Some wonder whether Qianhai, like the many rounds of the Closer Economic Partnership Arrangement (Cepa), will benefit global banks and mainland businesses rather than local brokers, fund houses and insurers.
Last month, 15 banks were allowed to offer a combined 2 billion yuan (HK$2.46 billion) in loans to companies basing themselves in the special economic zone next to Shenzhen, where the Shenzhen government vowed in 2010 to build the "Manhattan of the Pearl River Delta".
Although bankers expect to cash in, brokers and insurers think differently. A local broker, who prefers to remain anonymous, is not optimistic.
"Like the many rounds of Cepa, it mainly benefits the international banks and the mainland financial firms. I do not see how Cepa nor Qianhai will greatly benefit the overall Hong Kong economy or financial services sector," the broker said.
He pointed out that while Cepa had proposed allowing Hong Kong-based futures brokers to set up joint ventures on the mainland, only a few such ventures were approved. By contrast, many mainland brokerages and fund houses had been allowed to set up in Hong Kong.
"Qianhai … benefits only the 15 banks involved, and the real purpose is to promote the internationalisation of the yuan. I do not see Beijing wanting to use Qianhai to help Hong Kong brokers or other financial firms develop in China," he added.
The broker believes Qianhai will ultimately become a property project, and that the companies which buy property there to set up offices will benefit from rising property prices rather than by developing their businesses.
But some brokers are fighting more aggressively for a slice of Qianhai's opportunities. The Hong Kong Securities Professionals Association last month signed an agreement with the Authority of the Qianhai Shenzhen-Hong Kong Modern Service Industry Co-operation Zone of Shenzhen for the two sides to work out proposals to attract Hong Kong and international financial firms to invest in Qianhai.
Christopher Cheung Wah-fung, the financial services sector legislator who led the association's delegation to the signing, said it would submit a report to Qianhai this month setting out a wish list.
"Hong Kong brokers would like to set up offices in Qianhai if they will be allowed to sell shares to mainlanders," Cheung said.
While Hong Kong lenders are able to offer loans only to Qianhai companies, but not to other mainland firms, Cheung hopes brokers can have a wider scope.
"If Hong Kong brokers or other financial firms can serve only Qianhai residents, it is not very attractive as Qianhai will have a population of only 800,000, which is similar to that of Sha Tin in Hong Kong," Cheung said.
Cheung said brokers would like their Qianhai offices to be able to serve other parts of Guangdong province and the mainland to tap into a bigger pool of clients. "This is how we can turn Qianhai into a city like Hong Kong," he said.
Insurance sector lawmaker Chan Kin-por said there had been no announcement so far on what Hong Kong insurers would be able to offer in Qianhai.
Beijing allows only international insurers with assets of at least US$5 billion to operate in China, a limit Chan says is too high. He hopes Qianhai will allow Hong Kong companies that can match the threshold for domestic insurers - capital of 200 million yuan - to operate there.
"We would like to see Qianhai allow Hong Kong based insurance companies with a lower amount of assets to be allowed to operate in Qianhai to serve clients in Guangdong province," Chan said.
John Tan, head of global markets for Standard Chartered in Hong Kong, is more optimistic about the overall impact of Qianhai on Hong Kong.
"Qianhai can turn into something big. It could become a window linking yuan fund flows with the offshore market," Tan said. "Shanghai's financial district of Lujiazui evolved from undeveloped farmland in the 1990s. Hence, Qianhai, in our perspective, also offers huge potential."