Hey Vagus, in your opinion..At age of 27. Workin 2 and a hlaf yrs as medical
officer. Is it too late to apply USMLE?
The longer version though is, well, longer. There are many, many things you have to consider, even before you consider the actual probabilities of getting into a residency in the specialty and location of your choice. The truth is, it's a long, long hard road.
For one, for many from the time of application to the USMLE steps 1 and 2, then the results, getting application formalities in order like CV, letters of references, interviews, etc etc things usually take a long while. We're probably talking about at least 2 years before you actually begin a residency. If you are sure this is what you'll want, then it's important to stick with the plan. I've known many in Malaysia who started off preparing for the USMLE 1, but between exhausting work, family obligations and the such, they run out of steam after a few months and abandon their plans.
The residency program themselves differ in length depending on specialty, but factor in at least 3 years. In the meantime, if you've already worked a few years in MOH, if you're at the point in your life when you're starting to make a stable foundation for yourself professionally and personally, you'll also have to ask yourself how much are you willing to sacrifice to begin training in the US. Unless you've had some certification most US programs will probably have you begin at internship level. Also, it's (in my opinion) easier to leave Malaysia the younger you are. Once you're a bit more established, especially if you're in a stable relationship, then it makes it all harder to leave, because the fact is though you may plan to return, a lot can happen in that 3-6 years of postgrad training and fate may change your mind.
However, (and I am biased of course) the training programs here are excellent for the most part. I liked it for their well-defined durations, curriculums, academic expectations and (unless you screw up and get expelled) a pretty-definite credentials at the end. You know, for example, once you're in you'll be a general or orthopedic surgeon in 5 years. So, obviously I think it's all well worth it, though I've had to sacrifice a lot along the way, especially the proximity and time with family part.
So, to answer your question, it's never too late to apply for a residency if you know what you're getting yourself into, and are willing to face the challenge. Age itself is not an issue- I had a 40 year old in my class in residency who was previously an ENT surgeon in Vietnam, who moved here and decided to do internal medicine instead!