And with the district council polls coming up in November, a review of attendance found that four out of the five lawmakers took part in just one or two panels in the past three years. Many other elected district councillors joined four or five panels.

Starry Lee Wai-king, the new chairwoman of the Democratic Alliance for the Betterment and Progress of Hong Kong, was the exception - she took part in four panels at the Kowloon City District Council.

Those in the super seats all agree on one thing: the workload is overwhelming. But they are divided on whether this electoral system - created in a last-minute compromise to save the city's political reform in 2010 - should continue as it is.

One of the lawmakers says the system is workable and at least means community concerns can be passed on to Legco more accurately, but another wants the trade-based seats abolished.

"Lawmakers in foreign countries who are elected by a territory-wide constituency normally focus more on policy issues. But under the system in Hong Kong, we are also required to pay close attention to community affairs," said Democratic Party veteran Albert Ho Chun-yan. "This clash makes it a very difficult task."

Ho's party colleague, James To Kun-sun, has been a lawmaker for the Kowloon West geographical constituency since the 1990s. He said his workload increased when he was elected via the district council (second) constituency in 2012 - with more requests for help from residents of other districts.

"One in eight voters in Hong Kong cast a vote for me. But at the same time, the voters in my district council constituency should always come first because I wouldn't be able to run for a super seat if I wasn't first elected to the district council," To said. He added there had been times when he was so overwhelmed by calls for help that he had to pass them on to party colleagues.

Frederick Fung Kin-kee, of the Association for Democracy and People's Livelihood, said he occasionally had to decline requests for assistance from other districts because he was not familiar with the situation there.

But Chan Yuen-han, of the Federation of Trade Unions, said although she took part in fewer district council panels, as a super-seat lawmaker she could be more effective by bringing local voices to the legislature and senior government officials. "This system is workable, but we need more support and resources because we are held accountable for more voters," Chan said.

Although the super-seat lawmakers are elected by a citywide constituency, their annual budget for operating costs - currently at HK$2.06 million a year to cover staff salaries and office rents - is the same as other legislators.

The budget is usually reviewed every three to five years and any changes must be endorsed by the Executive Council.

Ho - who vowed to resign from his super seat to trigger a "de facto referendum" on the political reform - said he might consider running for a district council seat in November, but he would not seek re-election to Legco next year.

His colleague To, however, said he might try for re-election in order to win more seats for the pan-democratic camp - and to push for the functional constituency seats, including the super seats, to be abolished.

Other super-seat lawmakers wouldn't say if they planned to seek district council re-election as it would be seen as the start of campaigning, and any costs incurred over that period could be counted as election expenses.

Meanwhile, New People's Party lawmaker Michael Tien Pun-sun, also a district councillor in Tsuen Wan, said he was not interested in a super seat as it would be difficult to balance the duties. But party chairwoman Regina Ip Lau Suk-yee did not rule out fielding a super-seat candidate.