Well, according to their websites it's actually five minutes quicker to fly from NQY to SEN by EZY than to fly from NQY to LGW with flybe. Add in the swift passage through the terminal at SEN and on to the train and the SEN service should save quite a bit of time. LTN or STN would give access to more connenctions of course, but I guess you can get those via LGW so SEN can provide a jet link to London for the good folk of Cornwall - and provide a rapid link to those splendid surfing beaches for the good folk of Essex and East London. Fares look comparable too......