Some larger employers have polices in place regarding unpaid holiday for training and time off if called up, so checking HR is a good idea.
Regarding home life if you want to join do it with the realisation that you will be spending time away from home which if deployed can be up to eight months if you are concerned about this dont join.
You will meet some great people do some interesting things but do your research, with the defence cuts there is a chance that the reserves role will become relied on much more a good source of information regarding the RAF in general is
www.e-goat.co.uk
Oh and "stag on"