We used them a lot for flight only up to last year from Manchester paying between £250 and £300 each.
The service was excellent, good flight times, no queues at all at check in and at that time, the seating on board was really spacious as they used BMI aircraft with scheduled layout. They now use Monarch but reserve the extra legroom at the front for their holiday passengers. The prices are around £300 but that would now be for standard seats from Manchester - not sure about from the south, think they may still use BMI aircraft.
Really miss the great service they offered but I'm not paying top dollar for standard seats.