When I signed up, I wasn't 100% that the RAF was the career for me. However it was an easy decision to join because (broadly speaking) you only get one opportunity. As an earlier poster said, if it doesn't pan out, you can always leave. What you cannot do, as a bored middle-aged executive in a City firm with a nice house and a tedious rail commute, sat at your desk wondering 'what if?', is wind the clock back 30 years and become a RAF pilot instead.
In my view, you can't possibly make a decision on any of the following factors at your stage as there are simply too many variables:
- Location
- Nature of flying / aircraft type
- Flying hours
There are some things that are more certain:
- Camaraderie
- Satisfaction of serving and (potentially) playing a bit-part in history
- Income security
- Pension (despite recent changes, still better than private sector offerings)
- Variety (a "new job" every few years if you want it, without risk)
There are many downsides to the job, but there is still something rather special about being a military pilot.
I note that BA has just opened a self-funded pilot apprenticeship scheme. If multi-engine is your aim and you're not particularly bothered about serving Queen and country, I would go to them instead.