'doubt benefit' is correct and can be used in written English.
You can use this phrase to express disbelief or doubt about something that would typically be considered a benefit. For example, "I doubt benefit of getting a second job as the extra hours would be too tiring."
Such a donation would be a welcome gesture that would no doubt benefit many needy organizations.
We would no doubt benefit from having our president regularly questioned by other political leaders.
Pfeiffer, who is not black, has no relation to Harlem's past, but he can no doubt benefit its future.
One suggestion he makes is to ensure that local firms share in the construction of new nuclear plants—something that would, no doubt, benefit Rolls-Royce.
The conductor James Conlon has championed lost composers like Schulhoff with a missionary zeal, and these events will no doubt benefit from his erudition and commitment.
Either way, Skyteam card carriers would no doubt benefit from co-ordination with JAL, which would bring convenient transfers and possibly lower fares in the short term, at least.
"Doubt" benefits from its topical resonance.
There are, without doubt, benefits to Mr. Obama.
Philadelphia has no doubt benefited from playing the league's third-easiest schedule so far, but most of their wins have been by significant margins.
The pub has customers from all over the world, even out of season, and the nearby formations have "no doubt benefited the business", says Terry Kemp, who works there.The exact value of crop circles to the broader economy is unclear.
However, the name itself was an undeniable magnet for publicity, and attendance no doubt benefited from visitors more familiar with the fashion brand than with the art on display.
