A better question would probably be whether the British deserve a reputation for having a "good track record with counterinsurgencies." If we are only considering an end to combat operations without total withdrawal à la the United States in Vietnam, then the British do perhaps have a better track record. However, if we consider a successful counterinsurgency to be one in which combat operations end, and the final shape of the country is more in line with what the British wanted initially than the rebels, things become murkier.

Take the Kenya Emergency for example. The British succeeded in putting down the initial emergency with methods that could hardly be considered today, or even by the Americans just ten years later in Vietnam; detention camps where initial screening was based purely on ethnicity, followed by mass relocation into 'villages' that, for the most part, were closer to concentration camps than actual villages. This starved the rebels of support and supply, and ended the combat aspect of the insurgency.

And yet, despite this, the figure that would emerge to lead Kenya into independence was the very man the British had spent the entire 50s attempting to keep from such a position; Jomo Kenyatta. A convicted Mau Mau member became the Prime Minister, and first President of the country.[1] A successful counterinsurgency in terms of the battlefield, but rather unsuccessful in preserving the order the counterinsurgency was supposed to preserve.

In Malaya, the British did not really succeed in killing off the insurgency until Malaysia became independent. This removed the communists' most effective recruiting tool of a war of independence. Once again, the British failed to crush an insurgency, so much as they did give into its demands without admitting such a thing. Now yes, Malaysia did not become communist, so this is more of a "win" than the Kenyan Emergency.

I haven't read enough about Dhofar to really comment on it, but British involvement in Oman was far more limited than in Malaya and Kenya, as the country was a protectorate at the time, rather than a full-fledged colony.

It must also be kept in mind that much of Britain's reputation in handling decolonisation, and the violence that often came with it, is a testament to the common narrative fostered, at least in Britain, of a willing and calculated withdrawal from empire post-war. Much of that common narrative comes from the long-standing obsession of the British with prestige, and the requisite need to make everything about the process of imperial decline look good, organised, calculated, even in cases where British rule on the ground had practically evaporated by the last days of colonial status. In reality, the process, as is the case in all large historical events, was far more complex. It was confused, at times reluctant, at others almost over-eager, and oftentimes simply a complete mess.

TL;DR: Depending on how you define a successful counterinsurgency, the British post-WWII, as with most aspects of decolonisation, have a far more complicated track record than it would seem at first glance.

[1] - It should be noted that Kenyatta's actual ties with the Mau Mau were likely nowhere near what the British suspected, but that's a side-note as far as we are concerned in measuring British success at achieving their goals for Kenya.