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!