Spent some time in Kappaladi, just south of Kalpitya on the west coast in Feb this year.
It is lovely when there is wind, but it's a bit of a one trick horse. If there isn't any wind, there is NOTHING to do other than hang about with the other people at camp.
No tourist infrastructure to speak so you won't find restaurants or bars around at all.
Really depends on what you want out of your trip. I had just spent months roughing it around India and a month kitesurfing and relaxing on a beach in Sri Lanka was exactly what I needed. But we did have a period of 6 days, no wind.. I was pulling out my fingernails for entertainment by the end of it.
I'd also suggest doing your research when it comes to camps to stay at. PLUS, beware of the staff, I had money and credit cards stolen out of my cabin by staff members of the place I was staying. (but I'm sure they're niggles you're going to get in lots of places)..
In saying all of that - I want to go back to Sri Lanka, nothing beats the white sand and clear skies, and donkeys EVERYWHERE!
TKC