Flew with them as pax in Feb to Nice and return. Easy, BMI etc all full both ways due to a major conference in Cannes. Outbound was 85% full, return 35%, yet I know of people who flew to Marseilles with Easy and hired a car to get to Cannes.
No-one I met at the conference had any idea there were flights available - EU's marketing can not have been effective. Added to that Manston is miles from any decent sized centre of population. The plus side is that you can park long-term only 90 seconds from the check-in/arrivals!