The use of "OK" is widely used even among proper RP'ers .. with 'kay or kay also being used.
Following is a quote from Wikipedia about its origins:
Allen Walker Read established that the earliest verified use of okey in print was 1839, in the March 23 edition of the Boston Morning Post (an American newspaper). The announcement of a trip by the Anti-Bell-Ringing Society (a "frolicsome group" according to Read) received attention from the Boston papers. Charles Gordon Greene wrote about the event using the line that is widely regarded as the first instance of this strain of okey, complete with gloss:
The above is from the Providence Journal, the editor of which is a little too quick on the trigger, on this occasion. We said not a word about our deputation passing "through the city" of Providence.—We said our brethren were going to New York in the Richmond, and they did go, as per Post of Thursday. The "Chairman of the Committee on Charity Lecture Bells", is one of the deputation, and perhaps if he should return to Boston, via Providence, he of the Journal, and his train-band, would have his "contribution box," et ceteras, o.k.—all correct—and cause the corks to fly, like sparks, upward.
Read gives a number of subsequent appearances in print: seven were accompanied ("glossed") with variations on "all correct" such as "oll korrect" or "ole kurreck"; five appeared with no accompanying explanation, suggesting that the word was expected to be well-known to readers and possibly in common colloquial use at the time.
A year later, supporters of the American Democratic political party claimed during the 1840 United States presidential election that it stood for "Old Kinderhook". "Kinderhook" was a nickname for a Democratic presidential candidate, Martin Van Buren, a native of Kinderhook, NY. "'Vote for OK' was snappier than using his Dutch name."[4] In response, Whig opponents attributed OK, in the sense of "Oll Korrect", to Andrew Jackson's bad spelling.
The country-wide publicity surrounding the election appears to have been a critical event in okay's history, widely and suddenly popularizing it across America.
However, and importantly for one candidate etymology, earlier documented examples exist of African slaves in America using phonetically identical or strikingly similar words in a similar sense to okay.
So my question is, given the origins of OK (being an Americanised misuse of spelling for a change), and given that it's something related to the end of the 20th century, should "OK" and its derivatives be used in RP?
I'm uncomfortable using it myself, often resorting to "right", "indeed" and as Nariac suggested, "Very well", and similar more fuller words.
Any thoughts about it?
Mind you, I'm not being an RP elitist or something, but its use always bothered me.
Would love to hear what you peeps think.