As an Australian born in the mid 1980s, I admit I never saw the previous Mapp & Lucia TV adaption and I haven't unfortunately come across E.F. Benson's novels.
Having made that disclaimer and confessed my ignorance, I have to say I love watching this BBC version (even if only on my iPad in bed late at night). Having read other reviews, I am now inspired to read the novels and (time permitting) dig out the 80s TV adaptation. I think the casting and acting is fabulous. The town is colorful, picturesque and exiting. The take on 1930s fashion (costume design) I find eccentrically appropriate and exciting to behold. Overall very fun and amusing viewing!