I don't listen to Robert Elms so much now because ... well I'm at work, but I listened to his show pretty regularly for the first couple of years I lived in London and I reckon it played a part in my "getting" London and ending up staying here.
I do find him slightly irritating sometimes these days; don't know if that's because I've gotten 10 years more cynical/grumpy in the meantime or whether he's gotten slightly more pompous in the same period of time - but on balance he's great and even if it can grate occasionally, his enthusiasm has to be applauded. One of the few shows left on Radio London really worth listening to (actually I often recommend it to people new to London).