'undeniable benefit' is correct and usable in written English.
You can use it when talking about a clear advantage to something that is undisputed. For example: "One undeniable benefit of attending a top university is the network of professionals you have access to."
There is, though, an undeniable benefit some coaches cite when considering unorthodox plays.
In financial terms, the housing provides one undeniable benefit to colleges: less property damage.
But if all that seems reasonable to you, there is one undeniable benefit: a very nice price.
"Many customers do fast-forward through commercials when given the choice, and that is an obvious and undeniable benefit of a digital video recorder," said Peter Stern, executive vice president for new product development at Time Warner Cable.
One undeniable benefit to being on the Lettie, especially on a hot day in June: "It's better than being in a classroom," said Narendra Grujjar, 15, who was basking in the cool breeze.
One undeniable benefit of holding an early primary (or caucus) in a small state like New Hampshire is that any citizen has a chance to meet the candidates for president individually and interrogate them on the issues — even if the citizen is not, technically, a resident of that early voting state.
While the technology boom has bred hostility, it has also brought San Francisco undeniable benefits.
The early years of the Gore-Chernomyrdin Commission yielded undeniable benefits, along with controversy.
Regardless of your culinary persuasion, vegetarianism has produced some undeniable benefits for humanity.
While any new housing has undeniable benefits, some question whether the latest offerings are the right fit for Mott Haven.
"Globalization has undeniable benefits," said Bradford K. Smith, vice president for the peace and social justice program at the foundation.
