Syrian rebel commander Abdulaziz says U.S. military training helped his men kill at least 15 ISIS fighters in a recent battle near Aleppo.
Three months earlier, a similar engagement had gone the other way, with two of his men killed.
But his group, the Mujahideen Army, does not know if more of its men will be sent for training, such is the uncertainty surrounding plans for expanding aid to the "moderate" rebels who the United States hopes will fight ISIS in Syria.
The 50 fighters were the first from their group to attend the training in Qatar, part of an ostensibly covert CIA program to offer military support to vetted factions in opposition to President Bashar al-Assad.
"We felt the difference. Even the (ISIS fighters) felt the difference. I knew this because this time they withdrew," said Abdulaziz, 32, describing the day-long battle in October and giving only his first name.
"There has been an improvement in those 50."
Their month-long course in September included training on how to fire mortar bombs, heavy machine guns and American-made anti-tank missiles, in addition to battlefield tactics, and interviews aimed partly at assessing any radical leanings.
"We returned as one unit," said Abdulaziz, speaking at the Mujahideen Army's office in the southeastern Turkish city of Gaziantep, a short drive from the Syrian border. "The guys feel they are fighters at least. Their morale is higher."
The U.S. military says an opposition force of 12,000 to 15,000 is needed to retake Syria's east from ISIS.
But while the support has been useful, it falls short of what his group says they need to advance on the battlefield where they are outgunned by the government and ISIS.
His men returned with anti-tank TOW missiles, the hallmark of rebels vetted in the year-old CIA program. But like others, it says the support is insufficient.
"My message is: support the fighters properly, with ammunition and salaries. If they support us properly, they would not need to send the warplanes," Abdulaziz said, referring to U.S.-led air strikes against ISIS.
Mainstream rebels say the failure of the United States and its allies to support them adequately has allowed groups such as ISIS to dominate after 3-1/2 years of war.
Loosely defined as the "Free Syrian Army", these groups have suffered heavy losses fighting both government and jihadist forces.
Front Line
The Mujahideen Army is one of the biggest mainstream groups left in northern Syria. It says it has 6,000 personnel.
Northeast of Aleppo, its fighters are helping to hold a front line at the western edge of ISIS's self-declared "caliphate". ISIS advanced west towards Aleppo this summer before halting in September to attack the Kurdish town of Kobani.
The risk of ISIS resuming its westward march makes the need for more support all the more acute.
But more than two months since the U.S.-led alliance began air strikes against ISIS in Syria, such moderate groups do not know how or if they will fit into the new training plans being set up by the Pentagon.
The U.S. military says an opposition force of 12,000 to 15,000 is needed to retake the east from ISIS. A Pentagon spokesman said on Nov. 4 there had been progress in setting up the curriculum, readying the sites and securing trainers from the United States and other nations.
But the vetting process has yet to begin, suggesting it may take several more months to start.
The new program is separate from the CIA-run one that has already vetted and offered training to a number of groups. The CIA has declined to comment on this program.
Western and Arab states that oppose Assad have already been channeling what rebels describe as small amounts of military and financial aid to non-jihadist groups. These groups say they have already been through a vetting process.
"They asked about the lives of the fighters, where they worked before, everything about their lives," said Abdulaziz, describing conversations with the American trainers in Qatar.
"From these questions, they understand the mindset of this young man," he said. "We told them: 'You look at Islam as if it is only (ISIS). We told them (ISIS) is not Islam otherwise we wouldn’t be fighting them. They are not Muslims to begin with'."
For the rebels, the big questions now are whether they will be part of the new program and whether they will still receive support through the already established channels.
"We are completely in the dark," said a member of the Mujahideen Army's political office, who declined to be identified.
"Are they going to finish the vetting of the Mujahideen Army or not? Are they going to be creating a new vetting program? There is a lot of ambiguity," he said.
(Editing by Giles Elgood)