I went Papatura up in the north, Santa Isabelle province in April/May but we had no wind. In fact it was like the doldrums. But the flip side was that the surf was great. I highly recommend it. The previous trip we went to the Marovo lagoon in the Western province. Had a few days of good wind but I didn't have a kite with me. It's hard to find a spot to launch as trees grow right to the edge of the water and some very sharp coral rocks around. The people are great and it's very off the beaten track, we really loved it. What part are you off to?
Munda itself is a bit of a hole but all around is great and fantastic diving. It's easy to have a boat take you to where ever you want (in fact its the only transport). Check out gotours.com.au for some more info, they seem to know the area well. Buy some duty free booze when you go as it's hard to find over there. Remember there are no shops so take what you need. Also take a few gifts for the village kids. Have fun!
I spent 3 months there March-May this year, around Kolombangara and Gizo, Western Province. Surf was good, didn't see much wind above 12-15 knots. Apparently it does get trades but only in the peak winter months June-August. If you are going to be at Roviana, take a surfboard, spare everything, good first aid kit, (can't have too much bacteroban!). Skulls righthander is not far from Munda, and if you are going to be up at Gizo, call in and see Ben Livah at Ben's Surf Camp (www.facebook.com/BensSurfCamp), he's right on the beach at Pailongge which is arguably the best and most consistent right hand barrel in the Sols. Enjoy!