Around 150 people watched the debate at the Workers' Institute at the Black Country Living Museum on Tuesday night.
Among them was Dino Motti, aged 34, lives in Harborne and works as a doctor in Dudley. He said: "I came here without an idea on who to vote for.
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"I see all the candidates tried to define the differences between themselves. They all made good points. I was shocked to hear the turnout could be as low as 20 per cent, I hope their campaigns lead to more people being interested."
He added: "I would like to see the candidates speak more on public health. I'm still undecided on who to vote for."
Martin Jamieson, 48, from Tividale, said: "I think it is important to be as aware of what each candidate offered as possible, before voting."
Lib Dem supporter Mr Jamieson said he was considering voting for Conservative candidate Andy Street in order to prevent Labour from winning the election.
He added: "The issue which most interested me was transport. I think we need to quickly free up the congestion on our roads.
"Nobody ever makes money sitting in standstill in their cars. The M6 Toll has proved an interesting issue for debate between the candidates."
Christian Kiever, 48, from Dudley, said: "I was impressed by some of the candidates. The Green Party candidate came across very well, but for me, I am a Labour supporter, and our man seems the most experienced."
David Boaz, 71, of Field Road in Tipton, said: "My intention is to vote Conservative - but I was impressed with most of the candidates. The event has come up with much to think about.
"I was particularly interested in the feelings of some of the candidates for the West Midlands to take back control of the region."