The pension contribution is better than some other companies, but not all their direct competitors. You really have to sit down and do some hard sums to figure out what is best for you, when you factor in time to command and the associated pay rise as well as your age and time to retirement. It's not an easy thing to assess.
In the past many ex-mil guys would leave the service at 38 with a pension, go to BA and leave at 55 with another pension(probably as a junior LH Capt). That will not happen any more as the goal posts have moved considerably - time to command has increased and pension is worse.