I spent a week there last July. Had an awesome time.
It was windy most afternoons. We had two afternoons of epic conditions (80kg me on a 4.7), three of pretty darn good conditions (5.5-6.5m), and two of good enough blasting conditions (7.5). When Vass is good, it is really, really good. Like a massive blasting party on the water with about 300 other windsurfers. It really is the luck of the gods though. July seems to look like the best month for reliable consistent wind. Later on in the season (towards autumn) the winds get less consistent. The longer you stay there, the better your chances of hitting epic Vass conditions.
When its blowing, the wind really slams down the side of the mountain into the sea and the wind is generally stronger the nearer you get to the mountain. It can be mega gusty near the base of the mountain as a result. 1km away from the mountain towards the port the wind can really drop off. It's a really weird local phenomenon. The lack of fetch means the water is generally pretty darn flat-ish for the wind speed of the day. Only when it got 4.7m weather did it seem bump and jumpy. It's not as flat though as, say somewhere like Dahab, which makes Vass really good fun, occasionally challenging, blasting conditions.
In terms of where to stay, you pay your money and take your choice. Club Vass is arguably the premiere resort location, with the best gear, best selection of gear, etc. But it is quite expensive! Cosmos is a bit cheaper and seems quite good. I stayed at The Surf Hotel and rented my gear through the "Surf School", which is attached to them. This place was great value and can be recommended. The rental gear selection here is nowhere near as vast as Club Vass though and occasionally some of their gear has signs of heavy use, whereas Club Vass' gear looked consistently pretty flash, as we walked past somewhat enviously every evening on the way to dinner in Lefkada port :lol:
Nevertheless, it was a great deal cheaper there and it got me through the week with a lot of smiles and stoke.
Lefkada town (at the port) has a great selection of greek food at differing price ranges. Eating out every night does add up the costs though.
In summary, I'd totally recommend Vass if you are into blasting and love mediterranian food. I will be going back, despite it being a long way from NZ.