Considering to Join the Reserves
I'm not there yet but I will be joining the Reserves when I'm out.
From what I can gather you need to attend 27 days (19 if joining a National unit) to qualify for your bounty (ex-Regs go straight for the max bounty of £1700), thats obviously on top of your daily pay rate.
There is a financial scheme for regulars to join the reserves and get a commitment bonus for it, but I think you have to join up within 1-2 years of leaving to qualify. It was all part of their plan to get current and competent blokes into the Reserves after the redundancy tranches.